31. How many atoms are present in 6.0g of magnesium? [Mg = 24, N.A = 6.02 x 10^23
- A. 1.20 x 10^22
- B. 2.4 x 10^22
- C. 1.51 x 10^22
- D. 1.51 x 10^22
Correct Option: Answer is C
32. The radio isotope used in industrial radiography for the rapid checking of faults in welds and casting is?
- A. Carbon-14
- B. Phosphorus-32
- C. Cobalt
- D. Iodine-131
Correct Option: Answer is B
33. Beryllium and Aluminium have similar properties because they
- A. Are both metal
- B. Belong to the same group
- C. Belong to the same period
- D. Are positioned diagonally to each other
Correct Option: Answer is D
34. mE + nF —–> pG + qH
- A. [E]m[F]/[G]p[H]q
- B. [E][F]/[G][H]
- C. [G]p[H]p/[E]m[F]
- D. [G][H]/[E][F]
Correct Option: Answer is C
35.
(I). 3CuO(s) + 2NH3(g) —–> 3Cu(s) + 3H2O(l) + N2(g)
(II). 2NH3(g) + 3Cl2(g) —–> 6HCl(g) + N2(g)
(III). 4NH3(g) + 3O2(g) —–> 6H2O(l) + N2(g)
The reactions represented by the equations above demonstrate the
- A. Basic properties of ammonia
- B. Acidic properties of ammonia
- C. Reducing properties of ammonia
- D. Oxidizing properties of ammonia
Correct Option: Answer is C
36.The salt that reacts with dilute hydrochloric acid to produce a pungent smelling gas which decolourizes acidified purple potassium tetraoxomanganate (VII) solution is
- A. Na2SO4
- B. Na2SO3
- C. Na2S
- D. Na2CO4
Correct Option: Answer is B
37. The refreshing and characteristic taste of soda water and other soft drinks is as a result of the presence of
- A. carbon(IV)oxide
- B. carbon(II)oxide
- C. Soda
- D. Glucose
Correct Option: Answer is A
38. Which of the following are mixtures?
I. Petroleum
II. Rubber latex
III. Vulcanizer’s solution
IV. Carbon sulphide
- A. I, II and III
- B. I, II and IV
- C. I and II only
- D. I and IV only
Correct Option: Answer is A
39. A balanced chemical equation obeys the law of
- A. Conservation of mass
- B. Definite proportion
- C. multiple proportions
- D.
- Conservation of energy
Correct Option: Answer is A
40. When air which contains the gases Oxygen, nitrogen, carbondioxide, water vapour and the rare gases, is passed through alkaline pyrogallol and then over quicklime, the only gases left are;
- A. Nitrogen and carbondioxide
- B. Rare gases
- C. Nitrogen and oxygen
- D. Nitrogen and the rare gases
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