Question

In breckenridge, Colorado, the typical atmopheric pressure is 50 torr. What is the boikiing point of water (delta H = 40.7 kJ/mol) in Breckenridge? I looked at the solution that Chegg already had but I was confused as to where they 70 degrees C vap pressure came from in step 1????

Answer 1

The typical pressure is 500- 520 torr. Please see the question once again and put the values...

if it is 50 still lets do calculation here....

ln(50 torr/760 torr)=((40,700j/mol)/(8.31 j/k*mol))*((1/373k)-(1/T2))

-2.72129542785 =4900 ((1/373)-(1/T2))

-0.0005553664 = 0.00268096514 - (1/T2)

-0.0005553664 - 0.00268096514 = -(1/T2)

-0.00323633154 = (1/T2)

Hence T2 =1/0.00323633154

T2 =308.991828445 K

this is temperature in K....

please see the pressure...if it is 500 then

ratio becomes -0.41871033485

i.e.

ln(500 torr/760 torr)=((40,700j/mol)/(8.31 j/k*mol))*((1/373k)-(1/T2))

-0.41871033485 =4900( 2.68*10^-3 - 1/T2 )

The answer will be T2= 361.605K