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

Question : 6

The observation that does not indicate a chemical reaction is

a) evolution of a gas

b) change of temperature

c) change of colour

d) None of these

Question : 7

Which of the following statements is true about chemical equation ?

a) Mass as well as atoms are conserved

b) Mass is conserved

c) Atoms are conserved

d) Molecules are conserved

Question : 8

The formula of sodium pyrophosphate is

a) Na₄ P₂O₇

b) Na₂ P₂O₇

c) Na₃ PO₄

d) Na₃ PO₃

Question : 9

The branch of chemistry which deals with study of physical properties and conditions is

a) nuclear chemistry

b) physical chemistry

c) analytical chemistry

d) pharmaceutical chemistry

Question : 10

The empirical formula of a compound is CH₂ . One mole of this compound has a mass of 42 grams. Its molecular formula is :

a) CH₂

b) C₃H₆

c) C₃H₈

d) C₂H₂