If I have 4.0 moles of a gas at a pressure of 5.6 atm and a volume of 12.0L. What is the temperature

Expert Answers
sharikendrick eNotes educator| Certified Educator

Step 1: List all of the information given in the question.

Pressure (P) = 5.6 atm

Volume (V) = 12.0 L

moles (n) = 4.0 moles

Temperature (T) = ?

Step 2: Choose a gas law formula to use. 

Since we're dealing with pressure, volume, moles, and temperature, we can use the Ideal Gas Law:

PV = nRT

Step 3: Look up any needed constants.

We have values for all of the variables that we will need to solve for temperature (T) except for R. R is the ideal gas constant. You can find the value for R by searching the internet or looking in your textbook. We want to make sure that we choose the version of R that contains the same units as were given in the question (L, atm, mol). In this case we will use R = 0.0821 L`*` atm/K`*` mol.

Step 4: Rearrange the equation to solve for T.

Algebraically rearrange the equation so that T is isolated. You can do this by dividing both sides by nR. This gives you the equation:

T = PV/nR

Step 5: Plug in all of the given values, as well as the value for R, and then calculate the answer.

T = (5.6 atm)(12.0 L)/4.0 mol)(0.0821 L`*` atm/K`*` mol) = 204.6 K 

Notice that temperature is given in the unit Kelvin (K). This is because Kelvin (K) is the temperature unit used in the R constant.