Year : 
2001
Title : 
Chemistry
Exam : 
WASSCE/WAEC MAY/JUNE

Paper 1 | Objectives

31 - 40 of 52 Questions

# Question Ans
31.

Which of the following constitutes an advantage in the use of hard water?

A. Formation of scum with soap

B. Furring of kettles

C. Blockage of water pipes

D. Formation of strong bones

D

32.

Sugars can be hydrolyzed at room temperature by the action of

A. mineral acids

B. strong bases

C. enzymes

D. oxidants

A

33.

If 10 cm 3 of distilled water is added to 10 cm3 of an aqueous salt solution, the concentration of the solution

A. increases

B. decreases

C. remains constant

D. doubles

B

34.

Which of the following reactions represents the change that occurs when a photographic film is exposed to sunlight?

A. Ag → Ag+ + e-

B. Ag+ + e- → Ag

C. 2Ag + Br22 → AgBr

D. Ag+ + Br- → AgBr

B

35.

Acidic industrial waste can be treated with

A. lime

B. brine

C. water

D. enthanol

A

36.

Waste plastics accumulate in the soil and pollute the environment because plastic materials are

A. insoluble in water

B. non-biodegradable

C. easily affected by heat

D. inflammable

B

37.

The conclusion from Rutherford's from radioactive substance alpha-scattering experiment is that

A. atoms are mostly empty space with a samll

B. emissions from radioactive substances consist of three main components

C. there is unclear pull on orbital electrons

D. electrons are deflected by both magnetic and electric fields

A

38.

If a metal R forms a compound with the formula R(NO3)2 the formula of its tetraoxosulphate (VI) is

A. R(SO4)2

B. RSO4

C. R2SO4

D. R2(SO4)3

B

39.

Which of the following decreases when a given mass of gas is compressed to half its initial volume?

A. Average intermolecular distance

B. Frequency of collisions

C. Number of molecules present

D. Atomic radius of each particle

A

40.

What volume of hydrogen will be produced if 100cm3 of ammonia is completely decomposed at constant temperature and pressure? The equation for the reaction is 2NH3(g) → N2(g) + 3H2(g)

A. 50cm3

B. 150cm3

C. 200cm3

D. 300cm3

Detailed Solution

According to the equation 2NH3 → N2 + 3H2 2x22400cm 3 of ammonia will produce 3x22400cm 3 of hydrogen if 100cm3 of NH3 is used H2 volume = 100/2x22400 x 3 x22400 = 150cm3
31.

Which of the following constitutes an advantage in the use of hard water?

A. Formation of scum with soap

B. Furring of kettles

C. Blockage of water pipes

D. Formation of strong bones

D

32.

Sugars can be hydrolyzed at room temperature by the action of

A. mineral acids

B. strong bases

C. enzymes

D. oxidants

A

33.

If 10 cm 3 of distilled water is added to 10 cm3 of an aqueous salt solution, the concentration of the solution

A. increases

B. decreases

C. remains constant

D. doubles

B

34.

Which of the following reactions represents the change that occurs when a photographic film is exposed to sunlight?

A. Ag → Ag+ + e-

B. Ag+ + e- → Ag

C. 2Ag + Br22 → AgBr

D. Ag+ + Br- → AgBr

B

35.

Acidic industrial waste can be treated with

A. lime

B. brine

C. water

D. enthanol

A

36.

Waste plastics accumulate in the soil and pollute the environment because plastic materials are

A. insoluble in water

B. non-biodegradable

C. easily affected by heat

D. inflammable

B

37.

The conclusion from Rutherford's from radioactive substance alpha-scattering experiment is that

A. atoms are mostly empty space with a samll

B. emissions from radioactive substances consist of three main components

C. there is unclear pull on orbital electrons

D. electrons are deflected by both magnetic and electric fields

A

38.

If a metal R forms a compound with the formula R(NO3)2 the formula of its tetraoxosulphate (VI) is

A. R(SO4)2

B. RSO4

C. R2SO4

D. R2(SO4)3

B

39.

Which of the following decreases when a given mass of gas is compressed to half its initial volume?

A. Average intermolecular distance

B. Frequency of collisions

C. Number of molecules present

D. Atomic radius of each particle

A

40.

What volume of hydrogen will be produced if 100cm3 of ammonia is completely decomposed at constant temperature and pressure? The equation for the reaction is 2NH3(g) → N2(g) + 3H2(g)

A. 50cm3

B. 150cm3

C. 200cm3

D. 300cm3

Detailed Solution

According to the equation 2NH3 → N2 + 3H2 2x22400cm 3 of ammonia will produce 3x22400cm 3 of hydrogen if 100cm3 of NH3 is used H2 volume = 100/2x22400 x 3 x22400 = 150cm3