adsense

GENERAL SCIENCE CHEMISTRY IN 41 50

41.       A mixture of sodium chloride and naphthalene can be separated, by

a)      Extraction with hot water

b)      Extraction with cold water

c)       Sublimation

d)      Steam distillation.

42.       The Ph of the solution obtained by dissolving pure sodium chloride in water is

a)      Acidic

b)      Basic

c)       Neutral

d)      Dependent on the amount of sodium chloride dissolved in water.

43.       Oxygen on reaction with non-metals forms oxides, which are

a)      Basic oxides

b)      Acidic oxides

c)       Amphoteric oxides

d)      Neutral oxides

44.       Biogas consists of mainly

a)      Methane

b)      Ethane

c)       Butane

d)      Carbon dioxide

45.       A gas is evolved when a   piece of zinc metal is placed in dilute sulphuric acid (H₂SO₄). What is the gas?

a)      Hydrogen

b)      Oxygen

c)       Water vapour

d)      Sulphur dioxide

46.       Turmeric (Hladi)rapidly becomes colorless on addition of

a)      Baking soda

b)      Vinegar

c)       Lemon juice

d)      Alcohol

47.       Metalloids are

a)      Alloys of alkali metals with other metals

b)      Colloids of metals

c)       Elements having some properties of both metals and non-metals

d)      Metals heavier than lead.

48.       Two reactants in a flask produce bubbles of gas; it turns lime water into milky. The reactants in the flask are

a)      zinc and hydrochloric an

b)      Magnesium carbonate and hydrochloric acid

c)       Magnesium nitrate and hydrochloric acid

d)      Magnesium sulphate and hydrochloric acid

49.       Yeasts bring about fermentation by the action of a complex enzyme known as

a)      Peroxidase

b)      Zymase

c)       Invertase

d)      Catalase

50.   The purity of 14 carat gold is

a)      14.6%

b)      30%

c)       58.4%

d)      75.5%

ANSWERS

41.C
42.C
43.B
44.A
45.A
46.C
47.C
48.B
49.B

50.C