Question

Which of the following relationships is not true for an ideal gas? Select one: 1. PV = constant when temperature and moles of gas are held constant 2. V/T = constant when pressure and moles of gas are held constant 3. nT = constant when pressure and volume are held constant 4. P/n = constant when volume and temperature are held constant 5. All the statements in this question are true

Answer 1

ANSWER:

The ideal gas equation is:

PV = nRT

where, R is a gas constant and its value is fixed 8.314 J/mol K.

1.) If number of mole (n) of gas and temperature (T) will be constant, then

PV = nRT

PV = constant x constant x constant

PV = constant.

Hence, statement (1) is true for an ideal gas.

2.) If number of mole (n) of gas and pressure (P) will be constant, then

PV = nRT

constant x V = constant x constant x T

V/T = constant.

Hence, statement (2) is true for an ideal gas.

3.) If pressure (P) and volume (V) will be constant, then

PV = nRT

constant x constant = n x constant x T

nT = constant.

Hence, statement (3) is true for an ideal gas.

4.) If volume (V) and temperature (T) will be constant, then

PV = nRT

P x constant = n x constant x constant

P/n = constant.

Hence, statement (4) is true for an ideal gas.

5. All the statements in this question are true (correct)