general concepts of chemistry - Category wise Question and Answer Practice Test with Solutions

Question : 6

Which of the following statement is not correct ? To prevent food from getting rancid, we

a) flush bags of chips with an inert gas

b) store the food in air-tight containers

c) add antioxidants

d) increase the temperature of the food

Question : 7

Which one is a combination reaction ?

a) Ca(OH)₂ + Na₂CO₃ ⟶ 2NaOH + CaCO₃ ↓

b) Formation of a mixture of carbon monoxide and hydrogen. When steam is passed over red hot iron.

c) Reaction of water with sodium metal to form sodium hydroxide and hydrogen.

d) Preparation of stannic chloride (Tin (iv) chloride) by passing chlorine gas into molten tin (Sn).

Question : 8

Which of the following reaction is endothermic?

a) CH₄ + 2O₂ ⟶ CO₂ + 2H₂O

b) C + O₂ ⟶ CO₂

c) CaCO₃ ⟶ CaO + CO₂

d) CaO + H₂ O ⟶ Ca(OH)₂

Question : 9

Valency of an atom or radicals is

a) its combining capacity

b) ionisation energy

c) electron affinity of atom

d) size of atom

Question : 10

An organic compound containing C, H and O gave on analysis C – 40% and H – 6.66%. Its empirical formula would be

a) CH₂O

b) C₃H₆O

c) CHO

d) CH₄O