chemistry help!

Question

A balloon is filled with H3FSi gas. If the balloon has a volume of 0.583 L at 22.0 degree Celsius and 75 atm, how many moles of H3FSi gas does it contain?

Answer 1

A balloon is filled with H3FSi gas. If the balloon has a volume of 0.583 L at 22.0 degree Celsius and 75 atm, how many moles of H3FSi gas does it contain?

PV = nRT

Solving for n (moles) of H3FSi we have...

n = PV/RT = (75 atm)(0.583 L) / (0.0821 Latm/Kmol)(295K) = 1.81 moles

If you want to know grams, just use the molar mass of H3FSi which is 50.1 g/mol

1.81 moles x 50.1 g/mol = 90.7 g

If you want the number of molecules, use Avogadro's number, 6.02x10²³ molecules/mole...

1.81 moles x 6.02x10²³ molecules/mole = 1.09x10²⁴ molecules

Answer 2

pV = nRT (ideal gas law)

p = 75

V = 0.583

R = 8.31 (physical constant)

T = 22 + 273 = 295 (needs to be in kelvin)

n = pV/RT , which you can find. This is the number of moles.