Question

Consider the following problem:

"Ammonia, NH3, is used as a fertilizer and as a refrigerant. What is the new pressure if 5 moles of ammonia with a volume of 750 mL at 1.50 atm is expanded to 7.50 L at constant temperature?"

In solving this with the ideal gas law, which R value will you use?

a. 8.31 L * kPa / K * mol
b. 0.0821 L * atm / K * mol
c. It doesn't matter which I choose for this problem, either of them will produce a correct answer.

Answer 1

c.

Step-by-step explanation:

The difference between the two is the measure of pressure. Atm (atmospheres) or kPa (kilopascals) both are measures of pressure. If we convert 8.31 kPa to atm, we get 0.0821 atm, hence both R values are the same and life is good.