Question

need help with part C

Part A 

Compute the specific heat capacity at constant volume of nitrogen (N) gas. The molar mass of N2 is 28.0 g/mol

 Part B 

You warm 1.75 kg of water at a constant volume from 23.0 "C to 29.0 "C in a kettle. For the same amount of heat how many kilograms of 23 0 Cair would you be able to warm to 29.0 C? Make the simplifying assumption that air is 100% N2

Part C 

What volume would this air occupy at 23.0 °C and a pressure of 1.02 atm?

Answer 1

C) We know 1 mole of nitrogen gas weigh 28 gm.

As you obtained in part B mass of air that could be warmed is 9.89 kg

So, number of moles in this amount of air is

9.89 x 103 n 28

From ideal gas law a gas at pressure P occupying volume V at temperature T we have

=nR

R is the universal gas constant and n is the number of moles.

We have,

P = 1.02 atm = 1.02 x 10 Pa

T 23 C (23 273) K = 296 K 1

Putting these values in the ideal gas law

9.89 x 103 1.02 x 105 x V x 8.31 x 296 28

9.89 x 103 x 8.31 x 296 or, V = m 3 1.02 x 105 x 28

or, V 3 8.518 т

$or,\ V=8.518\times1000\ L=8518\ L$

So the air would occupy a volume of 8520 L