Consider the gas law:

$\overline{){\mathbf{P}}{\mathbf{V}}{\mathbf{=}}{\mathbf{n}}{\mathbf{R}}{\mathbf{T}}}$, where n is the number of moles and R is the gas constant given by, R = 8.314 J•K^{-1}

The number of molecules is given by:

$\overline{){\mathbf{N}}{\mathbf{u}}{\mathbf{m}}{\mathbf{b}}{\mathbf{e}}{\mathbf{r}}{\mathbf{}}{\mathbf{o}}{\mathbf{f}}{\mathbf{}}{\mathbf{m}}{\mathbf{o}}{\mathbf{l}}{\mathbf{e}}{\mathbf{c}}{\mathbf{u}}{\mathbf{l}}{\mathbf{e}}{\mathbf{s}}{\mathbf{=}}{\mathbf{n}}{{\mathbf{N}}}_{{\mathbf{A}}}}$, where N_{A} is Avogadro's number.

The lowest pressure attainable using the best available vacuum techniques is about 10^{-}^{12}N/m^{2}.

At such pressure, how many molecules are there per cm^{3} at 13 °C?

Express your answer using two significant figures.

Frequently Asked Questions

What scientific concept do you need to know in order to solve this problem?

Our tutors have indicated that to solve this problem you will need to apply the Introduction to Ideal Gasses concept. You can view video lessons to learn Introduction to Ideal Gasses. Or if you need more Introduction to Ideal Gasses practice, you can also practice Introduction to Ideal Gasses practice problems.

What professor is this problem relevant for?

Based on our data, we think this problem is relevant for Professor Sirenko's class at New Jersey Institute of Technology.