Question #e7283

1 Answer

Answer:

#"0.32 g"# methane.

Explanation:

Take the ideal gas law

#PV = nRT#

and the equation for molar mass,

#MM = m/"mol"#

When you rearrange that equation, you get

#n = m/(MM)#

When you plug in the rearranged molar mass equation into ideal gas law, you get

#PV = (mRT)/(MM)#

I wasn't sure what you use for room temp and pressure, so I went with #"298 K"# and #"1 atm"#. Typically this would be calculated at STP (standard temperature and pressure, #"273 K"# and #"1 atm"#) because room temperature is subjective.

The molar mass of methane is #"16.04 g/mol"#; the ideal gas constant in atmospheres #(R)#, is #0.08206 ("atm" * "L")/("mol" * "K")#

Plug in all of these values into the rearranged ideal gas law:

#("1 atm")("0.48 L") = (m(0.08206 ("atm" * "L")/("mol" * "K"))("298 K")) / ("16.04 g/mol")#

Plug this into a calculator and for #m# (mass), you get #"0.32 g"#.