The pressure P2 at the temperature which CO2 gets solidifies is 0.857 atm.
Step-by-step explanation:
The relation between temperature T and the pressure P is that it is proportional to each other.
T ∝ P
As the temperature decreases, the pressure also decreases which is given by
T1 / T2 = P1 / P2
At the triple point of water, the temperature equals 273 K.
Consider T1 = 273 K, P1 = 1.20 atm
The temperature T2 of the CO2 solidifies equals 195 K
(273 / 195) = (1.20 / P2)
P2 = (195 x 1.20) / 273
P2 = 0.857 atm.
The pressure P2 at the temperature which CO2 gets solidifies is 0.857 atm.