The percentage of water of crystallization in ZnSO₄. 7H₂O is

• A) 33%
• B) 44%
• C) 55%
• D) 87%

A pair of compounds that can be used to generate a gas which has physiological effect on human beings is

• A. sodium trioxonitrate (V) and calcium chloride
• B. sodium dioxonitrate (III) and ammonium chloride
• C. sodium trioxonitrate (V) and ammonium chloride
• D. sodium dioxonitrate (III) and potassium chloride

When ammonium chloride is dissolved in water in a test tube, the tube feels colder showing that

• A. the solution is unsaturated
• B. sublimation has ocurred
• C. ammonia gas is evolved
• D. the process is endothermic

The best treatment for a student who accidentally poured conc tetraoxosulphate(vi) on his skin in the laboratory is to wash his skin with?

• A. with cool running water
• B. sodium hydroxide solution
• C. iodine solution
• D. sodium trioxonitrate(v) solution

Which of the following have a covalent bond?

• A) silver
• B) copper
• C) sodium
• D) diamond

The mass of one mole of (NH₄)₂CO₃is [O=16.0, N=14.0, C=12.0, H=1.0]

• A. 66.0g
• B. 76.0g
• C. 80.0g
• D. 96.0g

Which of the following aqueous methods cannot be used to distinguish between a strong acid and a a weak acid?

• A. Conductivity measurement
• B. Measurement of pH
• C. Measurement of heat of neutralization
• D. Action on starch iodide paper

Which of the following compounds is NOT an isomers of 2,2 dimethylbutane?

• A. 2-methylbutane
• B. 3-methylpentane
• C. 2,3-dimethylbutane
• D. 2-methylpentane

In the reaction above, an increase in pressure will

• A) decelerate the reaction
• B) Increase the yield of PCl₃
• C) increase the yield of PCl₅
• D) accelerate the reaction

Copper (ll) tetraoxosulphate (VI) is often added to swimming pools because it

• A. prevents the growth of algae
• B. coagulates suspended particles
• C. neutralizes dissolved gases in water
• D. reacts with any excess chlorine present