# A 410 ml sample of fluorine gas is heated from 25 C to 198 C at constant pressure, what is the final volume?

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A sample of fluorine gas with volume 410 ml at 25 C is heated to 198 C with the pressure remaining constant.

The volume (V) of n moles of a substance in the gaseous state, at temperature T and under pressure P is given by `V = (n*R*T)/P` where R is a constant equal to 8.314 J/(mol*K)

Here, n, R and P are constant; only T varies and increases from 298.15 K to 471.15 K.

The volume increases from 410 ml to `410*(471.15/289.15)` = 647.9 ml

**The final volume of the sample of fluorine at 198 C is 647.9 ml**

Use Charles' Law:

`V_1/T_1 = V_2/T_2`

Volume and temperature are proportionally direct. When one increases, so does the other. Make sure your units are in L and L.

`0.410/298 = V_2/471`

Solve for your unknown variable.

`V_2 = 0.648L`

Your final answer should have three sig figs!

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I'm sorry! I meant two! Your answer should be either 0.65 L or 650 mL

A 410 ml sample of fluorine gas is heated from 25 C to 198 C at constant pressure, what is the final volume?

Because pressure remains constant the whole time, I think we can ignore it and just look at volume and temperature. To keep this problem simple, let's look for a law that only involves volume and temperature.

Charles' Law:

Volume should be in liters and temperature should be in Kelvins.

Convert your numbers to proper units.

410 mL = .410 L

25 C = 25 + 273 K = 298 K

198 C = 198 + 273 K = 471 K

Plug in your values.

`(.410 L)/(298 K)=(V)/(471 K)`

Solve for V and you should get 0.65 L or 650 mL.

You would need to use Charles' Law:

V1= .410 L

T1= 298K

V2= x

T2= 471K

REMEMBER THAT THE UNIT FOR VOLUME HAS TO BE LITERS AND THAT THE UNIT FOR TEMPERATURE HAS TO BE KELVIN

Now plug in the numbers and do the math.

The answer will be 0.65 L or 650 mL.

Hope this helped!