Answer:
6.022 × 10²³ molecules of B₂H₆
Step-by-step explanation:
The given problem will solve by using Avogadro number.
It is the number of atoms , ions and molecules in one gram atom of element, one gram molecules of compound and one gram ions of a substance.
The number 6.022 × 10²³ is called Avogadro number.
For example,
18 g of water = 1 mole = 6.022 × 10²³ molecules of water
1.008 g of hydrogen = 1 mole = 6.022 × 10²³ atoms of hydrogen
B₂H₆ molecules:
21.63 g = one mole of B₂H₆= 6.022 × 10²³ molecules of B₂H₆