Question

active mass of 127g of Iodine present in 2 litre​

Answer 1

Answer:

Given : T=400 K, ν=1000 Hz

Atomic mass of Iodine m

I

=0.127 kg/mol

Let Iodine exists as I

n

.

So molar mass of I

n

, M

I

n

=nm=0.127n kg/mol

Distance between the nodes l=6.77 cm

So, wavelength of sound wave λ=2l=2(6.77)=0.135 m

Thus, velocity of sound wave v=νλ

∴ v=1000×0.135=135 m/s

Also, velocity of sound wave v=

M

I

n

γRT

∴ 135=

0.127n

γ(8.3)(400)

⟹ γ=0.7n

For n=1, we get γ=1.4 which is for diatomic gas.

Hence, Iodine is diatomic.

Thus answer is 2.

Answer 2

Explanation:

Given : T=400 K, ν=1000 Hz

Atomic mass of Iodine m

I

=0.127 kg/mol

Let Iodine exists as I

n

.

So molar mass of I

n

, M

I

n

=nm=0.127n kg/mol

Distance between the nodes l=6.77 cm

So, wavelength of sound wave λ=2l=2(6.77)=0.135 m

Thus, velocity of sound wave v=νλ

∴ v=1000×0.135=135 m/s

Also, velocity of sound wave v=

M

I

n

γRT

∴ 135=

0.127n

γ(8.3)(400)

⟹ γ=0.7n

For n=1, we get γ=1.4 which is for diatomic gas.

Hence, Iodine is diatomic.

Thus answer is 2.