Express your answer to three significant figures.

Question

A 24.8 g sample of nitrogen, N2, has a volume of 50.0 L and a pressure of 670. mmHg .

What is the temperature of the gas in kelvins?

What is the temperature of the gas in degrees Celsius?

Answer 1

This question is testing your knowledge of the Ideal gas law which states that PV=nRT, where P represents pressure in atms, V represents volume in liters, n represents moles, R represents a constant of 0.0821 with units ((atm*L)/(Kelvin*mol)), and T represents temperature in Kelvin.

The important points of this question are to convert the grams of N2 into moles of N2 and to convert the pressure from mmHg to atms. To convert N2 to moles, you first must determine the molar mass of diatomic nitrogen or N2. The molar mass is 28 grams. If we have 24.8 grams in this scenario, then the total moles of N2 would be 24.8/28, which comes out to about 0.886 moles.

Next, we have to convert from mmHg to atms for our pressure value. Since 1 atm is equivalent to 760 mmHg we can do 670/780 to get 0.859 atms of pressure.

With these new values, we can then solve for temperature using PV=nRT. Remember, the answer you calculate will be in Kelvin, so in order to convert back to degrees Celsius, you must subtract your value by 273.

I hope this helps