Question

9) Calculate the mass of following
a) 0.5 mole of N2 gas
b) 0.5 mole of Natom
c) 3.011 number of Natoms.​

Answer 1

Answer:

1 mole of N2 weigh 28 gram

0.5 mole weigh 14 gram.

1 mole of N atom weigh 14 gram

0.5 mole weigh 7.5 gram.

6*10 ²³ atoms of nitrogen weigh 14 gram

3.011*10²³ atoms weigh 7gram.

Answer 2

Number of Moles = Given Mass / Gram Atomic (or Molecular) Mass

∴ Given Mass = Number of Moles × Gram Atomic (or Molecular) Mass

Atomic Mass of N (Nitrogen) = 14

Molecular MAss of N₂ = 28

Q - Calculate the mass of the following:

a) 0.5 mole of N2 gas

→ Given Mass = Number of Moles × Gram Molecular Mass = 0.5 × 28 = 14 g

b) 0.5 mole of N atom

→ Given Mass = Number of Moles × Gram Atomic Mass = 0.5 × 14 = 7 g

c) 3.011 number of N atoms.​

→ Number of moles = Number of atoms / Avagadro's Number = 3.011 × 10²³ / 6.022 × 10²³ = 0.5

Given Mass = Number of Moles × Gram Atomic Mass = 0.5 × 14 = 7 g