Question

The root mean square speed of H, molecules at 25 °C is about 1.6 km/s. What is the ro a N2 molecule at 25 °C? is about 1.6 km/s. What is the root mean square speed of Urms - 3 PT 2082 1273 +25

Answer 1

part A

Root mean square velocity is C_rms =_{$\sqrt{\frac{3RT}{M}}$}

For Hydrogen gas

C_(H)= _{$\sqrt{\frac{3RT}{M_{H_{2}}}}$}

For Nitrogen gas

C_(N) = _{$\sqrt{\frac{3RT}{M_{N_{2}}}}$}

as temperature is equal

now,

$\frac{C_H}{C_N}$  = _{$\sqrt{\frac{M_{N_2}}{M_{H_2}}}$}

or, $\frac{C_H}{C_N}$ = _{$\sqrt{\frac{28}{2}}$}

or,  $\frac{C_H}{C_N}$ = √14 = 3.74

or, C_H= 3.74 × C_N

or, C_N= C_H ÷ 3.74  

or, C_N = ( 1.6 ÷ 3.74) = 0.427 Km/s = 427 m/s.

Hence root mean square velocity of Nitrogen gas at 25⁰c

= 427 m/s.

part B

Specific heat capacity of Aluminium = 0.902 J/g^oc

Then heat capacity of 1.05 Kg of Aluminium kettle

= mass (g) × specific heat capacity (J/g^oc)

= 1.05×1000×0.902

= 947.1 J/^oc.