State Avogadro’s Law. A cylinder contains 68g of ammonia gas at s.t.

1.	State Avogadro’s Law. A cylinder contains 68g of ammonia gas at s.t.p. 1. What is the volume occupied by this gas? 2. How many moles and how many molecules ammonia are present in the cylinder? [N = 14, H = 1]
Answer» Avogadro's law states that 'equal vol.of all gases under similar conditions of temperature and pressure contain the same no.of molecules.' (i) Molecular gram atom wt. of NH₃ = 17 gm 17 gm of NH₃ has vol. at s.t.p. = 22.4 lt. ∴ 68 gm of NH₃ has vol. at s.t.p = 22.4 x 68 /17 = 89.6 it. (ii) No. of moles in 68 g of NH₃ = 68/17 = 4 moles. ⇒ 1 mole of ammonia = 6.23 x 10²³ molecules ⇒ 4 moles of ammonia = 4 x 6.023 x10²³ =24.092 x 10²³molecules

State Avogadro’s Law. A cylinder contains 68g of ammonia gas at s.t.p. 1. What is the volume occupied by this gas? 2. How many moles and how many molecules ammonia are present in the cylinder? [N = 14, H = 1]

Answer»

Avogadro's law states that 'equal vol.of all gases under similar conditions of temperature and pressure contain the same no.of molecules.'

(i) Molecular gram atom wt. of NH₃ = 17 gm

17 gm of NH₃ has vol. at s.t.p. = 22.4 lt.

∴ 68 gm of NH₃ has vol. at s.t.p = 22.4 x 68 /17 = 89.6 it.

(ii) No. of moles in 68 g of NH₃

= 68/17 = 4 moles.

⇒ 1 mole of ammonia = 6.23 x 10²³ molecules

⇒ 4 moles of ammonia = 4 x 6.023 x10²³

=24.092 x 10²³molecules