The heat energy produced when the human body metabolises 1 gram of fat is

23.          The heat energy produced when the human body metabolises 1 gram of fat is

A.            30 KJ

B.            1 KJ

C.            39 KJ

D.            29 KJ

Answer: Option C

24.          What are the number of moles of CO2 which contains 16 g of oxygen?

A.            0.5 mole

B.            0.2 mole

C.            0.4 mole

D.            0.25 mole

Answer: Option A

Explanation:

One mole of CO2 has mass of 44 g and 32 g of O2. So 16 g of O2 have 22 g of CO2 or 0.5 moles of it.

25. The main use of salt in the diet is to

A.            make the taste of food better

B.            produce in small amounts the hydrochloric acid required for the digestion of food

C.            ease the process of cooking

D.            increase the solubility of food particles in water

Answer: Option B

26. The monomer of polythene is

A.            vinyl chloride

B.            ethylene

C.            ethyl alcohol

D.            None of the above

Answer: Option B

27. The luster of a metal is due to

A.            its high density

B.            its high polishing

C.            its chemical inertness

D.            presence of free electrons

Answer: Option D

28. The number of water molecules present in a drop of water (volume 0.0018 ml) at room temperature is

A.            1.568 x 103

B.            6.023 x 1019

C.            4.84 x 1017

D.            6.023 x 1023

Answer: Option B