00:02
Hello, so the i do gas equation is pv equals nrt, right? so if you look at the graph, the slope of the graph is pressure over temperature.
00:14
So if i rearrange this, this is going to be equal to p over t, or if you like changing p over changing t, which is the slope.
00:27
Oops, this is a second changing t, yeah? that is equal to nr over v.
00:41
So this is ideal, right? because it's constant throughout.
00:50
Pressure is changing, temperature is changing, whilst nr remains constant.
00:58
So that's fairly ideal.
01:00
Or you can also decide to, you know, get the slope at different points.
01:07
There has to be the same, right? because that is what this equation is about because originally this equation is about pv over t is a constant where this k it doesn't change okay and this one is the graph is linear right and so it obeys yeah that's equation at any temperature if you find pv over t at any temperature it's got to be the same.
01:43
You have to take this loop at two different points.
01:46
And you get the same value.
01:49
So that is that for, let's say, 1a.
01:55
If you go to 1b, we'll find the mass.
02:04
So we use pv plus nrt.
02:12
Like i said, because we are using the graph, then we're going to be using changing p over changing t.
02:17
That's going to be equal to nr over v so the slope you can take the whole line for the pressure for the changing pressure is going to be 200 minus 100 and then the changing of volume it's going to be 500 minus 250 that is the slope that is equal to nr n is mass over molar mass i can replace that with m r over mv what are we finding we're finding the uh the second signing the mass first let's talk about this so uh this is going to be 100 over 250 that's 10 over 25 that's 2 over 5 it plus mr over mv so we're finding mass m so we find in mass m that's going to be equal to 2 over 5 times m over r.
03:39
So you have 2 over 5 times the monomass was given us 4 over r.
03:53
R is a constant 8 .314.
03:57
So this is how you get the mass and that will be in grams.
04:04
So let's see...