# Problem: An open flask sitting in a lab fridge looks empty, but we know that actually it is filled with a mixture of gases called air. If the flask volume is 1.50 L, and the air is at standard temperature and pressure, how many gaseous molecules does the flask contain?

###### FREE Expert Solution
98% (417 ratings)
###### FREE Expert Solution

We’re being asked to calculate the number of air molecules inside a 1.50 L flask at standard temperature and pressure.

Recall that standard temperature and pressure (STP) is defined as 1 atm and 0 ˚C

For this problem, we need to do the following:

Step 1: Calculate the moles of air using the ideal gas law.

Step 2: Calculate the number of air molecules using Avogadro’s number.

98% (417 ratings)
###### Problem Details

An open flask sitting in a lab fridge looks empty, but we know that actually it is filled with a mixture of gases called air. If the flask volume is 1.50 L, and the air is at standard temperature and pressure, how many gaseous molecules does the flask contain?

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 Standard Temperature and Pressure concept. You can view video lessons to learn Standard Temperature and Pressure Or if you need more Standard Temperature and Pressure practice, you can also practice Standard Temperature and Pressure practice problems .

What is the difficulty of this problem?

Our tutors rated the difficulty of An open flask sitting in a lab fridge looks empty, but we kn... as medium difficulty.

How long does this problem take to solve?

Our expert Chemistry tutor, Dasha took 4 minutes to solve this problem. You can follow their steps in the video explanation above.

What professor is this problem relevant for?

Based on our data, we think this problem is relevant for Professor Mandelshtam's class at UCI.