The above apparatus consists of three temperature jacketed 12.315 litre bulbs connected by stop
cocks. Bulbs 'A' consist of NH3(g) , CO2(g) & N2(g) at 27ºC and a total pressure of 60 atm. Bulb 'B'
and 'C' are empty and maintained at temperature of –73ºC and –173ºC respectively. Initially stop-
cocks are closed and volume of the connecting lines is zero.
Given :
(i) NH3(g) liquifies at –20ºC, CO2(g) liquifies at –80ºC and N2(g) liquifies at –180ºC.
(ii) Vapour pressure of NH3(l)
at –73ºC = 1 atm
(iii) Vapour pressure of NH3(l)
at –173ºC is negligible
(iv) Vapour pressure of CO2(l)
is negligible
(v) On opening stop-cock (i) only, the pressure in containers becomes 17 atm and, on opening both
stop-cocks pressure decreases to 4 atm
what is the value of ( n NH3+ nCo2- nN2) (where n represents number of moles) in the initial mixture ?
