Exercise 1

Question 16 :

The Latin word formica means ant. The name formic acid is derived from this Latin word because

A). this acid, in ancient times, was used to eliminate ant-hills
B). this corrosive acid is secreted by ants to drive away their enemies
C). this acid was first obtained by the distillation of ants
D). ants are attracted by the odour of this acid
Answer : Option C

Question 17 :

The ore which is found in abundance in India is

A). monazite
B). fluorspar
C). bauxite
D). magnetite
Answer : Option A

Question 18 :

The inherited traits of an organism are controlled by

A). RNA molecules
B). nucleotides
C). DNA molecules
D). enzymes
Answer : Option C

Question 19 :

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

Question 20 :

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.