Dinitrogen difluoride gas is collected at 22.0 degree C in an evacuated flask with a measured volume of 25.0L. When all the gas has been collected, the pressure in the flask is measured to be 0.170atm. Calculate the mass and number of moles of dinitrogen difluoride gas that were collected. Be sure your answer has the correct number of significant digits.

0.176 mol dinitrogen difluoride 11.616 g dinitrogen difluoride

Explanation:

Assuming Dinitrogen difluoride behaves ideally, we can use PV=nRT to solve the problem:

P = 0.170 atm V = 25.0 L n = ? T = 22°C ⇒ 22+273.16 = 295.16 K

0.170 atm * 25.0 L = n * 0.082 atm·L·mol⁻¹·K⁻¹ * 295.16K

n = 0.176 mol

With the number of moles of dinitrogen difluoride we can calculate the mass, using its molar mass:

We can deduce the formula knowing that "di"=2 ⇒ Dinitrogen = N₂ & Difluoride = F₂ Molar mass = 2*14 + 2*19 = 66 g/mol

0.176 mol * 66 g/mol = 11.616 g