Question

Two tanks of equal volume contain equal mass of oxygen and nitrogen at 127°C. Find the ratio of pressure in two tanks.

Answer 1

Given: V = V_N, m_o = m_N, M_o = 32, M_N = 28

T₁ = T₂ = T = 127°C = (127+273)K = 400K

PV = nRT

P_oV = n_oRT            ...(i) (For oxygen)

P_NV = n_NRT         ...(ii)  (For nitrogen)

Dividing eqn (i) by eqn (ii), we get,

`(P_oV)/(P_NV)=(n_oRT)/(n_NRT)`

`P_o/P_N=n_0/n_N`

`P_o/P_N=m_o/M_o dividem_N/M_N          ...(∵m_o = n_oM_o  "&" m_N=n_NM_N)`

`P_o/P_N = m_o/M_o xxM_N/m_N`

But m_o = m_N      ...(given)

`P_o/P_N=M_N/m_N`

`=28/32`

`P_o/P_N=7/8`