#color(blue)("STP"#

STP is currently #0^@"C"# or #"273.15 K"#, which are equal, though the Kelvin temperature scale is used for gas laws; and pressure is #"10"^5color(white)(.)"Pascals (Pa)"#, but most people use #"100 kPa"#, which is equal to #10^5color(white)(.)"Pa"#.

You will use the **ideal gas law** to answer this question. Its formula is:

#PV=nRT#,

where #P# is pressure, #V# is volume, #n# is moles, #R# is a gas constant, and #T# is temperature in Kelvins.

#color(blue)("Determine moles"#

You may have noticed that the equation requires moles #(n)#, but you have been given the mass of #"CO"_2"#. To determine moles, you **multiply the given mass by the inverse of the molar mass** of #"CO"_2"#, which is #"44.009 g/mol"#.

#5.0color(red)cancel(color(black)("g CO"_2))xx(1"mol CO"_2)/(44.009color(red)cancel(color(black)("g CO"_2)))="0.1136 mol CO"_2"#

#color(blue)("Organize your data"#.

**Given/Known**

#P="100 kPa"#

#n="0.1136 mol"#

#R="8.3145 L kPa K"^(-1) "mol"^(-1)"#

https://en.wikipedia.org/wiki/Gas_constant

#T="273.15 K"#

**Unknown:** #V#

#color(blue)("Solve for volume using the ideal gas law."#

Rearrange the formula to isolate #V#. Insert your data into the equation and solve.

#V=(nRT)/P#

#V=(0.1136color(red)cancel(color(black)("mol"))xx8.3145 color(white)(.)"L" color(red)cancel(color(black)("kPa")) color(red)cancel(color(black)("K"))^(-1) color(red)cancel(color(black)("mol"))^(-1)xx273.15color(red)cancel(color(black)("K")))/(100color(red)cancel(color(black)("kPa")))="2.6 L CO"_2"# rounded to two significant figures due to #"5.0 g"#