Sodium and its compounds

Sodium is a typical alkali metal. It occurs naturally in its ores chiefly as sodium chloride (common salt), sodium trioxonitrate(V) (Chile saltpetre) and sodium trioxocarbonate(IV) (soda ash). Sodium is extracted industrially by the Downs Process. Here, common salt is electrolysed in the molten condition. Calcium chloride is added to common salt to serve as a flux (to bring the melting point of common salt from 800°C to about 600°C). In the molten sodium chloride are Na+ and Cl- ions.

Sodium is used:

i. In the manufacture of lead(IV)tetraethyl, an anti-knock addictive used in petrol.

ii. In sodium vapour lamps (having intensity yellow illumination).

iii. In the production of titanium needed for the manufacture of heat-resistant alloys in rockets.

iv. In an alloy for making coolants for nuclear reactors.

Sodium has some important compounds (e.g NaCl, NaOH, Na2SO4, Na2CO3) that are useful industrially.

1. Sodium chloride (NaCl): When pure, it is not deliquescent (dampness is due to impurities (like MgCl2) which are deliquescent). It is a convenient starting material for manufacturing compounds like caustic soda, washing soda, baking soda and salt-cake. It is also used for the preparation of chlorine gas and hydrogen chloride needed for the manufacture of bleaching agents and fine chemicals. In addition, sodium chloride is used in salting out process in soap making or in solvent extraction of organic substance from water.

2. Sodium hydroxide (NaOH) is prepared industrially by the electrolysis of brine (a saturated solution of sodium chloride). The pellet is deliquescent. Its dissolution in water is exothermic. The resulting aqueous solution is alkaline (turns red litmus blue).

Sodium hydroxide is used in the manufacture of soaps (saponification). It is also used in the textile industries for treatment of cotton. Also, an aqueous sodium hydroxide solution is used in qualitative analysis to form the hydroxides of metal ions in solution as precipitates. This facilitates the identification of some actions in unknown samples.

3. Sodium tetraoxosulphate(VI) (Na2SO4):

It is prepared in the laboratory by neutralizing sodium hydroxide solution by dilute H2SO4. The hydrated form is the Glauber's salt, Na2SO4.10H2O.

Sodium tetraoxosulphate(VI) is used:

i. In the manufacture of glass (a mixture of two silicates e.g. Na2SiO3 and CaSiO3)/

ii. In the manufacture of sodium sulphide (by heating it with coke).

Sodium sulphide is used for stripping the hair from hides and for making shaving powder.

iii. In drying the ethereal layer during solvent extraction of organic compounds from water.

4. Sodium trioxocarbonate(IV) (Na2CO3):

It is obtained industrially by the Solvay process. The raw materials are concentrated brine (NaCl), ammonia gas (NH3) and limestone (CaCO3) which yields quicklime (CaO) and carbon(IV)oxide (CO2) when heated. The process involves essentially the following steps:

i. formation of ammoniacal brine when brine is saturated with ammonia gas.

ii. Reaction between the ammoniacal brine and carbon (IV) oxide (produced by heating limestone) to form sodium hydrogen trioxocarbonate(IV) and ammonium chloride.

iii. Sodium hydrogen trioxocarbonate (IV) (not very soluble in water) is filtered from the reaction mixture and the washed.

iv. Heating of sodium hydrogen trioxocarbonate (IV) to sodium trioxocarbonate (IV) and carbon (IV) oxide (which is recycled). Sodium trioxocarbonate (IV) is stable to heat i.e. not decomposed on heating.

v. If the anhydrous sodium trioxocarbonate (IV) (soda ash) is dissolved in hot water and allowed to cool, it gives the crystalline form (washing soda).

The important uses of sodium trioxocarbonate (IV) are:

i. Softening of water for domestic purposes.

ii. Manufacture of glass (formation of silicates). The mixture of Na2SiO3, CaSiO3 and unreacted SiO2 constituent the glass.

iii. Manufacture of caustic soda.

Calcium and its compounds

Calcium is a typical alkali earth metal. It occurs as calcium trioxocarbonate (IV) in different forms: chalk, limestone, marble, calcite, Iceland spar and aragonite. It also occurs as calcium tetraoxosulphate (VI) e.g. gypsum, anhydrite. However, it is extracted industrially by the electrolysis of calcium chloride (a by-product from Solvay process), using graphite anode (also the container) and iron cathode. It is a silvery white metal. The density is 1.55g per cm3 and the melting point is about 850°C. It is not as reactive as sodium and so it is not necessary to keep it below the surface of petroleum oil (in contrast to sodium). However, a white film of oxide is formed on the surface on exposure to air. Calcium compounds generally burn with s brick-red flame.

Some of the important reaction of calcium are:

i. In air: it forms calcium oxide (quicklime).

ii. With water: calcium metal is used in the extraction of thorium and in steel casting (as deoxidizer). The important compounds of calcium are calcium oxide (CaO), calcium hydroxide (Ca(OH)2), calcium trioxocarbonate (IV) (CaCO3), calcium tetraoxosulphate (VI) (CaSO4) and calcium chloride (CaCl2).

1. Calcium oxide (lime, quicklime) CaO, is a white solid, made industrially by the action of strong heat on limestone (CaCO3).

It is a refractory substance (it will not melt even when heated to a very high temperature) hence its use in producing light (limelight). Its important reactions are:

i. With water, slaked lime Ca(OH)2 is formed.

This reaction is called slaking. The slaked lime is changed to lime-water if water is added and filtered..

Because quicklime is basic and hygroscopic, it is used as the drying agent for ammonia gas.

ii. With silica: CaO + SiO2 —> CaSiO3

2. Calcium hydroxide, Ca(OH)2 is a white powder, prepared by addition of water to calcium oxide. Its dissolution in water is exothermic. It is sparingly soluble in water but the solubility decreases with increasing temperature. It is basic hence gives reactions expected of bases (e.g. neutralization with aqueous mineral acids). The compound is useful in many ways:

i. In agriculture, to reduce acidity in soils (liming).

ii. In preparation of calcium trioxocarbonate (IV) e.g. chalk.

iii. In the making of mortar by builders.

3. Calcium trioxocarbonate (IV), CaCO3, occurs naturally as marble, chalk, limestone and in many other forms such as stalagmites and stalactites from the roof and floor of carvers. It is a white solid which is practically insoluble in water. Some of its reactions are:

i. With dilute acids (HCl and HNO3); it evolves carbon (IV) oxide (CO2).

ii. With water containing dissolved CO2, it dissolves to give soluble calcium hydrogentrioxocarbonate(IV):

Calcium trioxocarbonate (IV) is used:

i. In the extraction of iron using the blast furnace.

ii. In the manufacture of cement.

iii. In the Solvay process of manufacturing sodium trioxocarbonate (IV).

4. Calcium tetraoxosulphate (VI), CaSO4, is a white solid. It occurs naturally as anhydrite (CaSO4) and gypsum (CaSO4.2H2O), known as plaster of Paris (POP). This involves heating gypsum to a temperature between 100°C and 200°C.

Plaster of Paris is used medically in making casts to maintain joints in a fixed position. It is used industrially for cement and wall-plasters.

5. Calcium chloride, CaCl2, is a white solid. The solution is prepared by adding marble to dilute HCl until a little of marble remains.

The mixture is filtered. The evaporation of the filtrate to dryness gives the fused solid (anhydrous CaCl2). This is very deliquescent hence its use as a drying agent for most gases (except ammonia with which it reacts).

Calcium and its compounds

Calcium is a typical alkali earth metal. It occurs as calcium trioxocarbonate (IV) in different forms: chalk, limestone, marble, calcite, Iceland spar and aragonite. It also occurs as calcium tetraoxosulphate (VI) e.g. gypsum, anhydrite. However, it is extracted industrially by the electrolysis of calcium chloride (a by-product from Solvay process), using graphite anode (also the container) and iron cathode. It is a silvery white metal. The density is 1.55g per cm3 and the melting point is about 850°C. It is not as reactive as sodium and so it is not necessary to keep it below the surface of petroleum oil (in contrast to sodium). However, a white film of oxide is formed on the surface on exposure to air. Calcium compounds generally burn with s brick-red flame.

Some of the important reaction of calcium are:

i. In air: it forms calcium oxide (quicklime).

ii. With water: calcium metal is used in the extraction of thorium and in steel casting (as deoxidizer). The important compounds of calcium are calcium oxide (CaO), calcium hydroxide (Ca(OH)2), calcium trioxocarbonate (IV) (CaCO3), calcium tetraoxosulphate (VI) (CaSO4) and calcium chloride (CaCl2).

1. Calcium oxide (lime, quicklime) CaO, is a white solid, made industrially by the action of strong heat on limestone (CaCO3).

It is a refractory substance (it will not melt even when heated to a very high temperature) hence its use in producing light (limelight). Its important reactions are:

i. With water, slaked lime Ca(OH)2 is formed.

This reaction is called slaking. The slaked lime is changed to lime-water if water is added and filtered..

Because quicklime is basic and hygroscopic, it is used as the drying agent for ammonia gas.

ii. With silica: CaO + SiO2 —> CaSiO3

2. Calcium hydroxide, Ca(OH)2 is a white powder, prepared by addition of water to calcium oxide. Its dissolution in water is exothermic. It is sparingly soluble in water but the solubility decreases with increasing temperature. It is basic hence gives reactions expected of bases (e.g. neutralization with aqueous mineral acids). The compound is useful in many ways:

i. In agriculture, to reduce acidity in soils (liming).

ii. In preparation of calcium trioxocarbonate (IV) e.g. chalk.

iii. In the making of mortar by builders.

3. Calcium trioxocarbonate (IV), CaCO3, occurs naturally as marble, chalk, limestone and in many other forms such as stalagmites and stalactites from the roof and floor of carvers. It is a white solid which is practically insoluble in water. Some of its reactions are:

i. With dilute acids (HCl and HNO3); it evolves carbon (IV) oxide (CO2).

ii. With water containing dissolved CO2, it dissolves to give soluble calcium hydrogentrioxocarbonate(IV):

Calcium trioxocarbonate (IV) is used:

i. In the extraction of iron using the blast furnace.

ii. In the manufacture of cement.

iii. In the Solvay process of manufacturing sodium trioxocarbonate (IV).

4. Calcium tetraoxosulphate (VI), CaSO4, is a white solid. It occurs naturally as anhydrite (CaSO4) and gypsum (CaSO4.2H2O), known as plaster of Paris (POP). This involves heating gypsum to a temperature between 100°C and 200°C.

Plaster of Paris is used medically in making casts to maintain joints in a fixed position. It is used industrially for cement and wall-plasters.

5. Calcium chloride, CaCl2, is a white solid. The solution is prepared by adding marble to dilute HCl until a little of marble remains.

The mixture is filtered. The evaporation of the filtrate to dryness gives the fused solid (anhydrous CaCl2). This is very deliquescent hence its use as a drying agent for most gases (except ammonia with which it reacts).

Allotropes, Alloys and Ores of metals and non-metals

Both metals and non-metals show polymorphism or allotropy. This is the occurrence of an element in more than one form but in the same physical state. These forms are called polymorphs or allotropes.

Elements                      Major Allotropic Forms

Carbon                          Diamond and Graphite

Sulphur                          Rhombic sulphur

                                        Monoclinic sulphur

Tin                                  White tin and Red tin

Oxygen                           Dioxygen (Oxygen)

                                        Trioxygen (Ozone)

Phosphorus                   White phosphorus

                                         Red phosphorus

All the allotropes of an element have the same chemical properties even though they have different appearances or crystalline strictures. For instance, diamond (a hard form of carbon) and graphite (a soft form of carbon) can be shown to be the same element by combustion whereby a sample of each allotrope is burnt in excess oxygen. The product in each case is carbon(IV)oxide.

Metals are at times mixed intimately with other metals or non-metals to form alloys. The alloys combine the strength and the properties of the constituent elements.

Examples:

Alloys                       Constituent Elements

Brass                            Copper and Zinc

Bronze                          Copper and Tin

Steel                              Iron and Carbon

Duralumin                    Aluminum, Magnesium,

                                      Manganese and Copper

Sodium Amalgam       Sodium and Mercury

Zinc Amalgam              Zinc and Mercury

It should be noted that an amalgam is an alloy of mercury and another metal.

The form in which a metal occurs naturally is known as the ore. Metals can be removed or extracted from their ores by various means depending on their degree of activity. The activity series is the arrangement of elements in the decreasing order of reactivity or electropositivity or metallicity.

Those metals that are highly or moderately reactive do not occur free in nature but rather they occur in form of compounds in their ores.

The compounds found in ores are usually oxides or sulphides or trio of at on area (IV) of metals. These ores are either concentrated (by floatation) or roasting (heating in air) and then reduced chemically or electrolytically to release or free their metals. Elements in this category include potassium, sodium, calcium, aluminium and iron.

Ores                          Element sought

Haemitite                          Iron

Casseterite                       Tin

Bauxite                        Aluminum

Zinc blend                        Zinc

Galena                             Lead

Malachite                      Copper

However, there are other metals that have low reactivity and so they are usually found free in nature. Such metals include Platinum and Gold.

Metalloid are elements that are neither distinctly metallic nor clearly non-metallic e.g. Silicon, Arsenic, Tellurium, etc. The properties of metalloids are intermediate between those of metals and those of non-metals. For instance, they are semiconductors rather than being good conductors or nonconductors of electricity.

Deliquescent, Hygroscopic and Efflorescent Compounds

These are substances composed of two or more kinds of atoms (elements) joined together in a definite grouping.

The properties of a compound are distinct and different from those of the individual elements that are combined in its make-up.

There are several millions of compounds known. These compounds are derived from the elements e.g. water consists of hydrogen and oxygen atoms in ratio 2 to 1; common salt consists of sodium and chlorine atoms in ratio 1 to 1.

Compounds are usually classified in a number of ways:

Based on the behavior when exposed to the atmosphere, compounds are classified into three: deliquescent, hygroscopic and efflorescent.

Deliquescent compounds are those compounds that absorb moisture from the atmosphere and form the solutions of tjr compounds e.g. sodium hydroxide pellets, anhydrous calcium chloride and iron(III)chloride.

Hygroscopic compounds are those that absorb moisture from the atmosphere and become wet. Their ability to absorb water from air is less than that of deliquescent compounds. Hence the solid ones from pasty substances and not solution while the liquid ones become diluted e.g. sodium trioxonitrate(V), copper(II)oxide and concentrated tetraoxosulphate(VI)acid.

Efflorescent compounds are compounds that give out their water of crystallization to the atmosphere at ordinary temperatures e.g. sodium trioxocarbonate(IV)decahydrate loses nine of its ten moles of water of crystallization on exposure to air.

It should be noted that all deliquescent substances are also hygroscopic but not all hygroscopic substances are deliquescent. Hygroscopy is the ability of a substance to draw water vapour to itself and become wet. Both hygroscopic and deliquescent substances have this ability.

However, if a substance goes beyond being wet and becomes a solution in the course of drawing water to itself, it shows deliquescency.

Deliquescent and hygroscopic compounds are used as drying agents for gases in the laboratory. For instance, concentrated tetra of soul phage(VI)acid is the usual drying agent for acidic gases e.g. sulphur(IV)oxide, calcium oxide is commonly used as the drying agent for the alkaline gas, ammonia. Also, desiccants in desiccators are deliquescent or hygroscopic substances e.g. silica gel, calcium oxide, fused calcium chloride and phosphorus(V)oxide.

Physical and chemical properties of metals and non-metals

There are distinct substances that cannot be spit-up into simpler substances. Such substances consist of only one kind of atom. There are over one hundred elements known to date. Each of the elements is usually symbolized by a capital letter or a capital letter followed by a small letter derived from the English or Latin or Greek name of the element concerned e.g. Hydrogen (H), Sodium (Na), Copper (Cu), Uranium (U), Antimony (SB), Neon (Be), etc.

The elements can be categorized in several ways.

- Based on natural radioactivity, elements are classified into two: radioactive and non-radioactive elements.

Radioactive elements are those that undergo a spontaneous decay or degradation followed by the emission of one or more of the radiations (Alpha, Betta, Gamma).

Such elements include Radium (Ra), Uranium (U), Francium (Fr), Polonium (Po) and Thorium (Th).

Non-radioactive elements do not degrade or emit any radiations. They have stable nuclei and would therefore not undergo radioactive decay e.g. Sodium (Na), Calcium (Ca), etc.

- Based on properties, elements are classified into three: metal, non-metals, and metalloids.

Metals are elements that are ionized by electron loss e.g. Potassium, Sodium, Calcium, lead, etc.

They possess the following physical properties:

i. Ductility and malleability. Hence they are useful in making wire cables and fabrication in construction works.

ii. Good conductor of heat and electricity due to the presence of free mobile electrons in their lattice. They are therefore useful in making cooking pots, boilers and electric cables.

iii. Hard solids with high melting points/boiling points except sodium, which is soft, and mercury, which is a liquid metal.

iv. Lustrous (with silvery colour) hence useful in jewelry and in metallic paints because of its reflectivity.

v. Some of them make a sound note, when struck (sonorous) e.g. copper, iron, and aluminum. Such metals are therefore useful in making musical instruments.

vi. None of the metals are soluble in any ordinary solvent without a chemical change.

The general chemical properties of metal are:

i. Electropositive i.e. loss electron(s) to become ionized hence reducing agents.

ii. Most of the metal s combine with oxygen to form basic oxides e.g. CuO, MgO and CaO. However some metallic oxides are amphoteric e.g. ZnO, PbO. Such oxides react as both acid and base.

iii. Combine with chlorine to form electrovalent chloride e.g. NaCl.

iv. Form metallic hydrides that are ionic.

v. Replace the hydrogen in an acid if more than electropositive than hydrogen.

Non-metals are elements that ionize by electron gain e.g. hydrogen, oxygen, chlorine, bromine, carbon, etc.

Non-metals are therefore oxidizing agents (except a few of them) since they undergo reduction in their ionization process

The general physical properties of non-metals are:

i. Brittle i.e cannot be hammered into sheets (non-mallaeble) or drawn into wires (non-ductile).

ii. Non-conductors of heat and electricity because they do not possess free mobile electrons. However, graphite (a form/allotrope of Carbon) is a good conductor of electricity because it contains free mobile electrons in its lattice.

iii. Mainly gases (e.g. hydrogen, oxygen, nitrogen, chlorine) though some of them exist as solids or liquids. For instance, bromine is a liquid at room temperature, iodine is a soft violet solid, sulphur is a yellow solid, graphite and diamond are solids. While graphite is soft, diamond is the hardest known natural substance.

iv. Most of the non-metals are dull and cannot be polished but diamond (an allotropic firm of carbon) can be polished (lustrous) and can therefore used in jewelry.

v. Non-sonorous.

vi. Have low density though some of them are heavy e.g. diamond.

vi. Some non-metals dissolve slightly in water without reaction (e.g. oxygen) though some of them dissolve with water (e.g. chlorine, bromine).

Some of the general chemical properties of non-metals are:

i. They are mainly oxidizing agents.

ii. Form acidic oxides mainly e.g. carbon(IV)oxide, sulphur(IV)oxide, nitrogen(IV)oxide. The acidic oxides are known as acid anhydrides (compounds that dissolve in water to produce an acidic solution or a solution whose pH is less than 7).

iii. Non-metals combine with other non-metals to form covalent compounds e.g. ammonia, carbon(IV)oxide, hydrogen chloride.

Heating profile of a solid

The temperature at which vibrations of a particles of a solid become so great such that the mutual attractive forces are overcome and the particles break free from the fixed lattice positions and slide over one another in a liquid state is called melting point (m. pt). At this point, the solid state and the liquid phases are in equilibrium. Even though heat is continuously supplied to the solid, the temperature is constant at the time of melting.

Generally, the heat absorbed by a substance in changing from one phase to another is called the latent heat (hidden heat). The amount of heat absorbed, which causes the change of phase to occur at the melting point, is called the heat of fusion. The magnitude of this heat energy depends on the nature of the solid and the strength of the attractive forces between particles.

When heated, some solids however vaporize directly without passing through the liquid phase. On cooling, the vapour also turns to the solid phase. The phenomenon is known as sublimation. Solids having usually high vapour pressure exhibit this property. Examples of such solids include iodine crystal, ammonium chloride crystal, naphthalene, camphor and dry ice (solid carbon (IV) oxide).

Similarly, boiling point (b. pt) is the at which the liquid and vapour phases are in equilibrium. The boiling point of a liquid depends on the prevailing external atmospheric pressure. The lower the external pressure, the lower the boiling point of a liquid and vice-versa. The amount of heat absorbed that causes change of phase (liquid – vapour) to occur at the boiling point is the heat of vaporization.

Properties of Matter

Properties tell us what a substance is or what a substance can do. The properties of matter are classified as either physical or chemical.

Physical properties tell us everything about what a substance is, when no change is occurring to its constituents. Such properties are observed with our senses or instruments or pieces of apparatus. Examples are: state of matter, colour, odour, taste, texture, hardness, solubility in water, melting point, boiling point, density, viscosity and spectroscopic patterns (IR, UV, NMR).

Chemical properties are those properties that tell us about what a substance can do as regards to whether or not the substance reacts with other substances. Examples are flammability, rusting of iron, precipitation, decomposition of water by an electric current.

Changes of Matter

The changes that matter undergoes are associated with properties. The change are therefore categorized into physical and chemical.

A physical change is one that alters the physical properties of matter (particularly the form and state). In many cases, the changes of state is easily reversible. Examples are changes of state such as boiling, melting, freezing, condensation, sublimation, magnetization of metals, breaking glass and cutting wood.

A  chemical change is one in which new kind of matter is formed. It us always accompanied by energy changes (evolution or absorption of energy in form of heat or light or both). The process is not easily reversible. Examples are: combustion, rusting of iron, precipitation and souring of milk.

Classification of Matter

Matter is anything that has mass and occupies space i.e everything seen or unseen.

On a broad basis, matter can be subdivided into two general categories: pure or distinct substances and impure substances (mixtures).

Pure substances are distinct substances having the following general properties:

i. All parts are the same throughout (homogeneous).

ii. Composition is definite.

iii. They cannot be easily separated by physical means.

iv. Separation by physical methods is not easy.

v. They have a unique set of physical properties (boiling point, melting point, density, physical state, spectroscopic properties, etc.).

Physical properties are, in fact, used as the criteria for determining the purity level of substances. Pure solid substances have sharp melting point or very narrow melting range (Example: a reasonable pure benzoic acid sample has a melting point of 122°C or a melting range 120°C to 122°C). However, impurities (contaminants) cause a depression in melting points and widening of the melting range of solid substances (Example: an impure sample of benzoic acid has a melting range 110°C to 118°C).

For liquid, the criterion for determining the purity level of samples is the boiling point or relative density. A reasonable pure liquid has a constant boiling point or a low boiling range (Example: 99°C or 98°C to 100°C for distilled water). Impurities cause an elevation of the boiling point and the widening of the boiling range of a hitherto pure liquid (Example: 99°C to 105°C for an impure water sample).

Pure substances are either elements or compounds.

State of Matter and Phase Changes

Chemist usually describe substances as matter. Each form of Matter is made up of aggregates of small particles called molecules. Molecules consist of one or more tiny particles called atoms. A molecules may be monoatomic (e.g. He, Ne, Ar) or diatomic (e.g. H2, O2, N2, Cl2) or polyatomic (e.g. O3, P4, S8). Hence:

Atoms >>> Molecules >>> Matter

Matter exists in three phases commonly referred to as the states of matter. These are gas, liquid and solid.

The particles (molecules) of a gas are very far apart and are held together by very weak attractive forces, those of a liquid are much more closely held together by stronger attractive forces, those of solid are most closely held together by very strong attractive forces.

The phase transfer processes are freezing, melting, boiling, condensation and sublimation.

Solid     >>>     Liquid     (Melting)

Liquid    >>>     Solid      (Freezing)

Liquid    >>>     Vapour    (Boiling)

Vapour   >>>     Liquid     (Condensation)

Solid     >>>     Vapour    (Sublimation).

We are going to learn more about matter in the next article

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Adverbial cluster

Adverbs are words that qualify verbs. They tell us more about an action.

Example: He carried the egg carefully

Sometimes, more than one adverb can describe va particular action. The three major classes of adverbs are:

Adverbs of Manner: which tell us how an action takes place;

Adverbs of Place: which tell  us where an action takes place; and

Adverbs of Time: which tell us when an action takes place.

When a number of adverbs comes together to describe an action, they should be arranged according to a specific pattern.

The formula is MPT where,

M=  Manner

P= Place

T= Time

This formula implies that the adverb of manner should come first, followed by the adverb of place and then adverb of time.

Examples: Re-arrange the adverbs in the following sentences.

See me by 2pm, in my office briefly.

See me briefly (manner) in the office (place) by 2pm (time).

Cut the yam from the bottom carefully.

Cut the yam carefully (manner) from the bottom (place).

Clean the glass tomorrow morning properly.

Clean the glass properly (manner) tomorrow morning (time).

Adjectival cluster

Adjectives are words used to modify, describe or qualify a noun. A number of adjectives can also come together to describe a particular noun. When this occurs, they should be arranged in a specific order. The formula is

OLWSASCPMON: Where:

O  = Others e.g. brilliant, clever, beautiful, etc.

L  = Length e.g. long, short, tall, high, etc.

W  = Weight e.g. heavy, massive, light, etc.

S  = Size e.g. big, small, large, medium, etc.

A  = Age e.g. old, new, ancient, primitive, archaic, modern, etc.

S  = Shape e.g. fat, slim, round, oval, spherical, etc.

P  = Participle e.g. dancing, jumping, cooked, discarded, etc.

M  = Material e.g. wooden, metal, earthen, plastic, ceramic, etc.

O  = Origin e.g. Nigerian, Japanese, Chinese, American, etc.

N  = Noun head e.g. John, table, car, cobra, etc.

Note that any adjective in "others" cannot fit into the other categories.

Examples:

Arrange this adjectives in the right order

1.  The woman would not part with her (discarded, earthen, black) pot.

Answer: The woman would not part with her black discarded earthen pot.

2. The hunter killed a (black, spitting, cobra, big).

Answer: The hunter killed a big black spitting cobra.

3.  The Carpenter made a ( polishes, round, wooden, brown, massive, English, high, table)

Answer: The Carpenter made a high massive round brown polished wooden English table.

4. I saw a (Italian, fair, beautiful, young-looking, shining, tall, slender, girl).

Answer: I saw a beautiful tall young-looking slender fair shining Italian girl.

We are going to be treating Concord in our next article. Stay tuned!

Concord in English

The term 'CONCORD' is derived from the name of an ancient Roman goddess called 'Concordia'. Concordia was a goddess of agreement, harmony and understanding. It is as a result of this that perhaps the term 'concord' is used to means agreement.

In grammar the term Concord is used to means agreement as well. The 'golden rule' of concord is that the subject of a sentence must agree with the verb of the sentence, such that, if the subject is singular, the verb will be singular and if the subject is plural the verb will be plural.

Note that, by 'singular subject' we mean a noun or pronoun without a plural marker such as 's' and is referring to a singular person, thing or idea e.g. table, boy. While plural subjects on the other hand, take markers showing or referring to more than one person, thing or idea. For example, tables, boys.

We should note that, unlike subjects realized typically by nouns, singular verbs take 's' or 'es' while plural verbs do not take 's' or 'es', both in their simple present forms. E.g. go (plural), goes (singular); eat (plural), eats(singular). The rules of Concord do not consider the past tense forms of verbs.

Whether the subject is singular or plural, if action is in the past, the verb will take no number indicator such 's' or 'es'. For example:

1.  John breaks glasses every day. (Singular  subject-singular simple present verb)

2.  John and James break glasses every day. (Plural subject-plural simple present verb)

3.  John broke glasses when he was a toddler. (Singular subject-simple past verb)

4.  John and James broke glasses when they were toddlers. (Plural subject-simple past verb)

You will observe that the verbs in example 3 and 4 above do not change even when there is a change in the number of the subject. It is because the verb is in a simple past tense. Simple past tense verbs are not affected by the number of the subject.

Actually, this agreement we talk about in concord transcends, the subject ad verb of the sentence. Other items are sometimes considered.

Concord in English involves:

i.  Subject-Verb Agreement

     -Subject verb agreement in number (singular number and plural number)

     -Subject verb agreement in person (first, second, and third person)

ii.  Antecedent Pronoun Agreement

In line with the following, we shall consider the following types of concord in our next articles.

Parenthesis Concord

Sometimes, some words may come between the subject of a sentence and the verb. Such words may hinder us from getting or selecting the appropriate verb that will agree with the subject. The obstructing information is what we refer to as parenthesis.

Examples:

1.  John, not his parents and siblings ____ around a. is b. are c. am

The answer is a 'is' because (not his parents and siblings) is the parenthetic information while 'John' is the subject and it is singular.

2.  It is I who ____ responsible for the quarrel.

To get the answer, we need to look for the subject requiring the 'x-verb' i.e. the verb we are looking for. Let us bracket the following words in the sentence.

(It) (is) I (who) am responsible for the quarrel

It is wrong to say: It is I who is responsible... It may sound 'sweeter' as some people would say or more pleasant, but it is wrong because the pronoun 'I' cannot agree with the auxiliary verb 'is', We cannot say: 'I is responsible'.

Only the auxiliary 'am' and its past tense 'was' should go with 'I' in this instance, except in a subjunctive relationship which will be discussed later.

3.  It is you who ____ being expected at the party a. am b. is c. are

Many students or speakers of English will take 'is' as answer thereby having:

'It is you who is being expected at the party' (wrong)

Let us use the same method as we have used earlier.

(It) (is) you (who) are being expected at the party.

'You' cannot agree with the auxiliary verb 'is' because it is regarded or used as a plural pronoun therefore, option c 'are' being a plural verb is the answer.

Also note these examples:

- (Not only John but even) his parents are good people.

- (Not only the teachers but even) the principal teaches well.

Subordination Concord

Subordination concord involves the use of subordinating conjunctions to join more than one subjects together. The rules stipulates that when a subordinating conjunction joins two subjects together, they are taken as one therefore, they take a singular verb. Examples of subordinating conjunctions or subordinators include: with, as well as, alongside, along with, together with, in conjunction with, in collaboration with, including, like, etc.

Examples:

i. Mr. Akpan with his children is traveling abroad. (Not 'are traveling...')

ii. The principal alongside the bursar steals money. (Not 'steal...')

iii. John as well as Mary sleeps late at night. (Not 'sleep...')

It should be noted that the determining subject is the first subject. The second is merely an attachment or a subordinate embedded in the first. Therefore, if the first subject is plural, the verb becomes plural.

Example: The teachers together with the principal travel every summer.

The verb 'travel' is plural because the first subject 'teachers' is plural.

Coordination Concord

This type of concord involves the use of coordinating conjunctions or coordinators to join more than one subject together. The rule stipulates that when two subjects are joined with coordinators, the verb is plural. A major example of coordinators is 'and'.

Example: Ojo and Ada are friends.

Note that this law only applies when the subjects refer to separate people or things. This means that sometimes, more than one subject can have the same identity.

For example: The pastor and president of the church ____ around. a. is b. are

The answer is 'a' and this is so because the 'pastor' and 'president' refer to the same person. The absence of article 'the' before the second subject'president' accounts for this assumption. Therefore, since the two coordinated subjects are having the same identity, they take a singular verb.

In the next article we will be treating topic on Words Often Misused.

Parenthesis Concord

Sometimes, some words may come between the subject of a sentence and the verb. Such words may hinder us from getting or selecting the appropriate verb that will agree with the subject. The obstructing information is what we refer to as parenthesis.

Examples:

1.  John, not his parents and siblings ____ around a. is b. are c. am

The answer is a 'is' because (not his parents and siblings) is the parenthetic information while 'John' is the subject and it is singular.

2.  It is I who ____ responsible for the quarrel.

To get the answer, we need to look for the subject requiring the 'x-verb' i.e. the verb we are looking for. Let us bracket the following words in the sentence.

(It) (is) I (who) am responsible for the quarrel

It is wrong to say: It is I who is responsible... It may sound 'sweeter' as some people would say or more pleasant, but it is wrong because the pronoun 'I' cannot agree with the auxiliary verb 'is', We cannot say: 'I is responsible'.

Only the auxiliary 'am' and its past tense 'was' should go with 'I' in this instance, except in a subjunctive relationship which will be discussed later.

3.  It is you who ____ being expected at the party a. am b. is c. are

Many students or speakers of English will take 'is' as answer thereby having:

'It is you who is being expected at the party' (wrong)

Let us use the same method as we have used earlier.

(It) (is) you (who) are being expected at the party.

'You' cannot agree with the auxiliary verb 'is' because it is regarded or used as a plural pronoun therefore, option c 'are' being a plural verb is the answer.

Also note these examples:

- (Not only John but even) his parents are good people.

- (Not only the teachers but even) the principal teaches well.

Subordination Concord

Subordination concord involves the use of subordinating conjunctions to join more than one subjects together. The rules stipulates that when a subordinating conjunction joins two subjects together, they are taken as one therefore, they take a singular verb. Examples of subordinating conjunctions or subordinators include: with, as well as, alongside, along with, together with, in conjunction with, in collaboration with, including, like, etc.

Examples:

i. Mr. Akpan with his children is traveling abroad. (Not 'are traveling...')

ii. The principal alongside the bursar steals money. (Not 'steal...')

iii. John as well as Mary sleeps late at night. (Not 'sleep...')

It should be noted that the determining subject is the first subject. The second is merely an attachment or a subordinate embedded in the first. Therefore, if the first subject is plural, the verb becomes plural.

Example: The teachers together with the principal travel every summer.

The verb 'travel' is plural because the first subject 'teachers' is plural.

Coordination Concord

This type of concord involves the use of coordinating conjunctions or coordinators to join more than one subject together. The rule stipulates that when two subjects are joined with coordinators, the verb is plural. A major example of coordinators is 'and'.

Example: Ojo and Ada are friends.

Note that this law only applies when the subjects refer to separate people or things. This means that sometimes, more than one subject can have the same identity.

For example: The pastor and president of the church ____ around. a. is b. are

The answer is 'a' and this is so because the 'pastor' and 'president' refer to the same person. The absence of article 'the' before the second subject'president' accounts for this assumption. Therefore, since the two coordinated subjects are having the same identity, they take a singular verb.

In the next article we will be treating topic on Words Often Misused.

Words Often Misused

1.  Lend/Borrow

Lend is used for the giver while borrow is used for the receiver. Thus means you lend to while we borrow from. For instance, if Mary gives money to John, it means Mary is lending to John while John who is receiving the money is borrowing from Mary.

2.  Fall/Fell

Fall means to drop down from a higher level or be defeated. The past tense is 'fell'. Fell is to cut down a tree or to bring down somebody on the ground. Example: an opponent in a boxing ring. The past tense is felled e.g. The former Vice-Chancellor felled some trees on campus.

3.  Steal/Rob

Steal is used when the action is quietly or secretly done without the use of arms or violence while Rob is used when it involves arms or violence.

4.  Latter/Later

Latter means being the second of two things while Later means at a time in the future after the time you are talking about.

5.  Hire/Rent

Hire means to pay money to use something for a short time such as a car while Rent means to regularly pay money to somebody so that you can continue to use what they own such as a house.

6.  Price/Prize

Price is the amount of money that you have to pay for am item or service while Prize is an award given to somebody who performs best in a competition.

7.  Sometimes/Sometime

Sometimes is an adverb which means occasionally rather than always e.g. Sometimes, I travel abroad. Sometime is an adjective which means a time that you cannot know exactly or a time that has not yet been decided e.g. I should travel abroad sometime next week.

8.  As/Like

As is used for a real identity e.g. The man is dressed as a Yoruba man: this means the man is really a Yoruba man. Like on the other hand is used for an imitated identity e.g. The man dressed like a Yoruba man: this means the man is not a Yoruba man but by his dressing, he looks like one.

9.  Everyday/Every day

Everyday is an adjective used to describe a noun. The two words are written together and when it is used, a noun comes after it e.g. This is an everyday event. Every day on the other hand is an adverb and the two words are separated e.g. I go to school every day.

10.  Talkative/Talker

Talkative is often used wrongly by most speakers of English. It is often used as a noun, whereas it should be used as an adjective. Talker is what we are supposed to use when we put an article before e.g. It is wrong to say: The girl is a talkative. It is because the word is an adjective which should not stand alone with an article. It could be written thus:

- The girl is a talkative person.

- The girl is a talker.

- The girl is talkative.

Since we cannot say: The girl is a beautiful, we cannot also say the girl is a talkative because they are both adjectives.

11.  Invaluable/Unvaluable

Invaluable means priceless, worthy or of a very high value or importance while invaluable if at all exists, would mean something that is worthless.

12.  Loose/Loosen/Lose/Lost

Loose is an adjective which means 'not firm' 'not tight'. It is often mistaken for Loosen which is a verb. When something is loosened, that is when it becomes loose. It us wrong to say: Help me loose the rope round the neck of the dog because it is too tight. Instead you say: Help me loosen the rope round the neck of the dog because it is too tight. I need it to he loose. Lose on the other hand is a verb in a present tense form meaning not to have possession of something anymore. The past tense is lost and the effect is loss. For instance, it is wrong to say: John, please don't lost my money. Instead you say: John, please don't lose my money. The sentence can then continue by saying: Last year you lost some and it was a big loss.

13.  Childish/Childlike

Childish is a behaviour typical or connected to a child. It is usually uncomplimentary or disapproving. It is usually used in a negative manner. For example: We all hate that man for his childish behavior. Childlike on the other hand means having qualities of a child usually used in a positive sense such as having the innocence of a child or the voice of a child e.g. His childlike behavior always earns him favour.

14.  Desirous/Desirable

Desirous means longing to have something e.g. The boy seems desirous if being a President. Desirable on the other hand means something that is worth getting e.g. Being a president is quite desirable.

15.   Ago/Since/For

Ago is used with numbers coming before it e.g. John travelled five days ago. Since on the other hand is used when we refer to a definite time. It does not require the use of numbers e.g. I have sat here since morning. For is used when a definite time to mentioned either in number or figure e.g. I have been here for ten days. It is wrong to say: I have been here for last week.

We will treat more on words commonly Misused has we move on.

English Sentences

I define sentence as a word or group of word beginning with a capital letter, ending with an appropriate punctuation mark such as full-stop, comma, question mark, or an exclamation mark, giving a complete sense with meaning. When a sentence is made up of just a word, such word must be a lexical finite verb. E.g. sleep, go, come, etc.

Types of Sentences

There are four classifications of sentences and these classifications are based on the structure of the sentences. They include:

- Simple sentences

- Compound sentences

- Complex sentences

- Compound complex sentences

Simple Sentences

A simple sentence is that which has a singular verb and expresses a single thought. It is made up of a single independent clause.

Note: An independent clause (also known as a main clause) is that clause which can stand on its own and make a complete sense while a dependent clause (also known as a subordinate clause) is a clause that cannot stand on its own to make a complete sense. A sentence is said to be simple when its structure comprises just one clause which must be an independent clause/main clause.

Example 1: I saw him.

Example 2: He went to the market.

Only a single thought or message is expressed in the sentences above and are conveyed through the verb saw and went respectively. It should therefore be noted that, the messages or thoughts in a sentence are expressed or conveyed by the verb.

Compound Sentences

This is made up of at least two independent clauses. This implies that the structure of a compound sentence comprises only independent/main clauses i.e. clauses that can stand on their own. Compound sentences express at least two thoughts or messages. The clauses in a compound sentence are joined by coordinating conjunctions. There are three major types of coordinating conjunctions and they include: and, but, or. Examples:

1. I saw him but I did not greet him.

There are two clauses in the sentence above joined by the coordinator 'but'. These two clauses can stand separately with each having a complete sense. We call such sentences compound sentences.

2. She went to the market but she did not buy oranges. (Two independent clauses)

3. You should sleep on the floor or you sleep on the bed. (Two independent clauses)

4. I saw Peter but he did not see me and I pretended. (Three independent clauses)

A compound sentence can also have commas as the conjunction e.g.

5. We came, we saw, we conquered.

Complex Sentences

These are sentences that are made up of one independent/main clause and one or more dependent clauses. The clauses in a complex sentence are usually joined by subordinators or subordinating conjunctions. Such subordinators includ: although, however, instead, when, etc. Examples:

1. I saw him (main clause) although I did not greet him (dependent clause).

2. He went to the market (main clause) when I was hungry (dependent clause) despite our quarrel (dependent clause).

Compound Complex sentences

These are sentences that contain at least two main clauses plus one or more subordinate clauses. These means that we should have a minimum of two main clauses and a minimum of one subordinate clause. Examples:

1. He went to the market (main clause) and he brought me oranges (main clause) although we were quarrelling (dependent clause).

2. He came (main clause) and we meet him (main clause) although we could not speak with him (dependent clause) because he was sick (dependent clause).

The classification of sentences discussed above is known as Structural Classification of Sentences. We have another classification known as Functional Classification of Sentences. It should be recalled that the structural classification is based on the clausal structure (make-up) of the sentence. The functional classification on the other hand is based on the functions of the sentences. There are four types of sentences under this classification and they include:

Declarative sentence: its function is information giving. For example: John is coming tomorrow.

In this sentences, the subjects are naturally fronted.

Interrogative sentence: its function is information demanding, e.g.

Is John coming home? (Polar interrogative)

What is your name? (Non-Polar interrogative)

In this sentences, the operators (auxiliary verbs) are naturally fronted in polar interrogatives while 'wh' words are fronted in non-polar questions.

Imperative Sentence: its function is to give commands. Examples:

Get out now. (Exclusive imperative)

Let's go now. (Inclusive imperative)

In these sentences, the predicators (verbs) are fronted for the exclusive imperatives while 'let' is fronted in the inclusive imperative. Imperatives naturally do not take subjects but do in some cases.

Exclamation Sentence: its function is expression of feelings. Example:

How lucky we are!

These sentences sometimes appear as interrogatives but they are not. They normally end with the exclamation mark.