0:00
Hi.
00:07
First question we are to calculate the number of moles in the balloon using the given information here.
00:14
We will use the ideal gas equation pv.
00:17
P is pressure, v, volume, is equivalent to n.
00:20
The number of moles are the ideal gas constant in t, the temperature.
00:24
So rearranging this to solve for n will have pv over rt.
00:28
So let's plug in the given values here.
00:31
Pressure is 1 atm, volume is 11 .5.
00:37
Liters r is 0 .0 8206 this is the ideal gas constant and it would be better if you memorize this as well temperature is 20 this is in degrees celsius so convert to kelvin by adding to 173 .15 now cancel some units you can cancel atm liters kelvin and our remaining unit is moles because we are solving for n so solving for this 1 times 11 .5 divided by 0 .08206 times 20 plus 273 .15.
01:17
This is 0 .47805.
01:22
This is moles.
01:25
Let's write our answer in three significant figures, 0 .478 moles.
01:33
And then we are to determine the volume of the balloon using the new volume of pressure and the temperature, we can use the combined gas law equation, p1, v1 over t1 is equivalent to p2 v2 over t2.
01:57
So we'll solve for v2, we'll have b1, b1, t2 over p2t1...