Question #2ed61
1 Answer
Explanation:
The idea here is that you need to use the molar volume of a gas at STP to determine what the molar mass of nitrogen gas is.
Next, you meed to use the ideal gaas law equation to find how many moles of nitrogen gas you have in that volume and at those specific conditions for pressue and temperature.
So, at STP, or Standard Temperature and Pressure, one mole of any ideal gas occupies exactly
This means that if
The ideal gas law equation looks like this
#color(blue)(PV = nRT)" "# , where
You need to find the mass of sample of nitrogen gas that
- occupies a volume of
#"5.6 L"# - has a pressure of
#"38 mmHg"# - has a temperature of
#273^@"C"#
Plug in your values and solve the ideal gas law equation for
#n = (38/760color(red)(cancel(color(black)("atm"))) * 5.6color(red)(cancel(color(black)("L"))))/(0.082(color(red)(cancel(color(black)("atm"))) * color(red)(cancel(color(black)("L"))))/("mol" * color(red)(cancel(color(black)("K")))) * (273.15 + 273)color(red)(cancel(color(black)("K"))))#
#n = "0.00625 moles"#
Now use nitrogen's molar mass to determine how many grams would contain this many moles
#0.00625color(red)(cancel(color(black)("moles"))) * "28 g"/(1color(red)(cancel(color(black)("mole")))) = color(green)("0.18 g")#