Chemistry Past Questions And Answers
If a reaction is said to be exothermic, which of the following statements is a correct deduction from the information?
- A. the reaction vessel gets hotter as the reaction proceeds
- B. ΔH for the reaction is positive
- C. the rate of the reaction increases with time
- D. the activation energy of the reaction is high
Which of the following gases is colourless, odourless and soluble in potassium hydroxide solution?
- A. NO2
- B. SO2
- C. NH2
- D. CO3
An element used in the production of matches is
- A) nitrogen
- B) aluminium
- C) copper
- D) sulphur
The following gases decolourize bromine water except
- A) C2H6
- B) C2H4
- C) C2H2
- D) C3H4
Apart from water, the other product(s) of the neutralization reaction between NaOH solution and nitrogen (IV) oxide is/are
- A) NaNO2
- B) NaNO3
- C) NaNO3 ?and HNO3
- D) NaNO2 ?and NaNO3
An aqueous solution of CaCI2 is
- A. acidic solution
- B. alkaline solution
- C. a buffer solution
- D. a neutral solution
X(g) → X−(g). The type of energy involved in the above transformation is? A. ionization energy B. sublimation energy C. lattice energy D. electron affinity
- A. ionization energy
- B. sublimation energy
- C. lattice energy
- D. electron affinity
Which of the following is not a property of magnesium oxide?
- A. High melting point
- B. Dissolution in polar solvents
- C. Presence of ionic bonds
- D. Low binding energy
Metal salts of long chain fatty acids are known as
- A) detergents
- B) double salts
- C) soaps
- D) grease
Aluminum is above iron in the electrochemical series, yet iron corrodes easily on exposure to air while aluminium does not. This is because aluminium
- A. has a lower density than iron
- B. is a better conductor than iron
- C. does not corrode spontaneously
- D. forms thin layer of inert oxide in moist air