Question

The number of gram atoms present in 81 g of aluminium is

• A.
  4 gram atoms
• B.
  3 gram atoms
• C.
  2 gram atoms
• D.
  5 gram atoms

Answer 1

The correct option is B

3 gram atoms
Gram atomic mass of aluminium = 27 g

Number of gram atoms $=\frac{\text{Given mass}}{\text{Gram atomic mass}}$

Number of gram atoms $=\frac{81}{27}=3$

Hence, the correct answer is option (b).