3

Maximum marks- 25

Maximum time-35 minutes

1.  What are the rules for writing the symbol of an element?      (3)

2.  Explain relative atomic mass and relative molecular mass.      (2)

3.  What is the relationship between mole, Avogadro number and mass?      (3)

4.  How do atoms exist?      (2)

5.  Define a mole. What is the importance of a mole?      (3)

6.  Calculate the mass of one atom of oxygen      (1.5)

7.  Calculate the mass of one ion of oxygen      (1.5)

8.  What do you understand by atomic mass and Gramatomic mass of an element?      (2)

9.  The formula of water is H2O. What do you understand by this formula?      (3)

10.  State the Law of conservation of mass and the Law of constant proportion with examples.      (4)