Question

The rms speed of the molecules in 1.3 g of hydrogen gas is 1600 m/s.

Answer 1

Answer:

Explanation:

1.3  g = 1.3 / 2 = .65 moles of hydrogen .

.65 moles = 6.02 x 10²³  x .65 molecules

Translational kinetic energy of one molecule = 1/2 mc² where c is rms speed = 1/2 x 2 x 1.67 x 10⁻²⁷ x ( 1600 )² = 42752 x 10⁻²⁵ J

Translational kinetic energy of .65  moles = 6.02 x 10²³  x .65 x 42752 x 10⁻²⁵ J

= 1673 J  approx .

B )  Total thermal energy and total translational kinetic energy are same so

Thermal energy of gas = 1673 J

C )  Net content of thermal energy = 1673 + 500 - 2000 = 173 J  

If c be the rms speed

  1/2 x 2 x 1.67 x 10⁻²⁷ x .65 x  6.02 x 10²³ c² =  173

6.534 x 10⁻⁴ c² = 173

c² = 264769

c = 514.56 m /s