Chemical equilibrium is attained when

• A. reactants in the system are used up
• B. concentrations of the products are greater than those of the reactants
• C. concentrations of the reactants and products remain constant
• D. reactants stop forming the products

A reducing agent is expected to

• A. decolourize acidified KMnO₄ solution
• B. decolourize acidified FeSO₄ solution
• C. liberate CI₂ from a chloride
• D. liberate CO₂ from NaHCO₃

Which of the following compounds is composed of Al, Si, O and H?

• A) Epson salt
• B) Limestone
• C) Clay
• D) Urea

Natural water collected from rivers and ponds contain oxygen, carbon (IV) oxide and

• A. nitrogen
• B. hydrogen
• C. chlorine
• D. sulphur

Octane number is highest in petrol containing a high proportion of

• A. heptane
• B. octane
• C. 2-methylpentane
• E. 2,2,4-trimethylpentane

Water is said to be temporarily hard when it contains

• A) Ca (HCO3)2 and Mg (HCO3)2 salts
• B) Ca (HCO3)2 and CaCO3 SALTS
• C) Mg(HCO3)2 and CaSO4 salts
• D) CaSO4 and Ca(HCO3)2 salts

Equal amounts of marble chips are reacted separately with 100cm3 of hydrochloric acid of different concentrations . if all the marble chips reacted, which of the following remained the same in each case?

• A. Average rate of evolution of gas
• B. Total mass of gas evolved during the reaction
• C. Time taken for the reaction to reach completion
• D. lnitial reaction rates

Which of the following atoms represents deuterium?

• A. No protons = 1, No of neutrons = 0, No of electrons = 0
• B. No protons = 1, No of neutrons = 0, No of electrons = 1
• C. No protons = 1, No of neutrons = 1, No of electrons = 1
• D. No protons = 1, No of neutrons = 2, No of electrons = 1

Hard water is water with high concentrations of dissolved ions, in particular calcium and

• A. magnesium ions
• B. nitrogen ions
• C. phosporus ions
• D. helium ions

Butene can be distinguished from benzene by reaction with:

• A) Hydrochloric acid
• B) Bromine water
• C) Potassium sulphate
• D) Sodium hydroxide