*I need help with this lab for my physics class. Here is the lab and questions below:

Pre-lab questions:

Can gas pressure ever go below zero?

Why? (Think about what causes the pressure and what absolute zero really means)

Open the simulation at: https://phet.colorado.edu/sims/html/gas-properties/latest/gas-properties_en.html

Give the bicycle pump at least 5 good pumps so there are lots of molecules whizzing around in the box.Then check the "Volume" button on the right hand side under Hold Constant.

Use the "heat" / "cold" bucket below the box to lower the temperature. Describe how fast the particles move as you decrease the temperature from 300 K to 150 K. Does their speed increase or decrease?

Does it make sense that the pressure went down as well?

Fill out the table below for several values of temperature and pressure in the 150 K to 300 K range.In the third column divide the pressure by the temperature

Temperature (K) Pressure (atm) Pressure / Temperature

__________ _________ __________

__________ _________ __________

__________ __________ __________

__________ __________ __________

__________ __________ __________

___________ __________ __________

Was the ratio of pressure to temperature a constant?

Now we will use the simulation to try to figure out what the temperature must be when the pressure is zero.

The fancy math-speak for this is extrapolation. We are trying to extend the red line along the grey dashed line.

All we need to do is fit an equation to this line of the form y=mx+b and find out what the temperature must be in order for the pressure to be zero. Fit a line to your data using any two points in the table above.By using hand or using an online tool such as http://www.webmath.com/equline1.html. Write the equation below:

In this equation, y represents pressure and x represents temperature. What value does x have to be when y = 0?

Does this agree with your predicted minimum temperature? ______________

The temperature at which the pressure line reaches zero is the lowest possible temperature; it is about - 273 ⁰C. On the Kelvin temperature scale this temperature is absolute zero, or 0 K.