Question

Given that 6.6 moles of carbon monoxide gas are present in a 43.3L container, what is the pressure of the gas (in atm) if the temperature is 84°C?

Answer 1

`"4.5 atm"`

Explanation:

This is a straightforward application of the ideal gas law equation.

`color(blue)(PV = nRT)" "`, where

`P` - the pressure of the gas
`V` - the volume of the gas
`n` - the number of moles of gas
`R` - the universal gas constant
`T` - the temperature of the gas - expressed in Kelvin

Notice that the question provides you with

• the number of moles of gas
• the volume of the container
• the temperature of the gas

This means that you have everything you need to calculate the pressure of the gas, provided that you know the value of the universal gas constant

`R = 0.082("atm" * "L")/("mol" * "K")`

Plug in your values into the above equation and solve for `P` - do not forget to convert the temperature from degrees Celsius to Kelvin!

`PV = nRT implies P = (nRT)/V`

`P = (6.6color(red)(cancel(color(black)("moles"))) * 0.082("atm" * color(red)(cancel(color(black)("L"))))/(color(red)(cancel(color(black)("mol"))) * color(red)(cancel(color(black)("K")))) * (273.15 + 84)color(red)(cancel(color(black)("K"))))/(43.3color(red)(cancel(color(black)("L"))))`

`P = "4.464 atm"`

Round this off to two sig figs, the number of sig figs you gave for the number of moles of gas

P = color(green)("4.5 atm")#