00:01
In this problem, we have n -pentane at one atmosphere.
00:05
We are also given the corresponding boiling points and melting points of our n -pentane.
00:11
Additionally, we are given the latent heat of vaporization and the latent heat of fusion.
00:18
We also have the corresponding specific heat values for our n -pentine in gas form and our n -pentine in liquid form.
00:28
So now, suppose that we have a certain sample of and pentane at 28 grams.
00:39
And we want to see how much heat is required if we have a starting temperature of negative 91.
00:50
Negative 91 .8 degrees celsius.
00:55
And we heat this sample of pentane to a final temperature of 64 .8 degrees celsius.
01:07
So how much heat will this take? so let's write in our equation for heat.
01:13
Q is equal to mass of the sample times specific heat, times the change in temperature, plus our mass times the respective latent heat.
01:26
And what we're going to do is break down our calculations for our total q in segments of q1, q2, and q3.
01:39
So in our q1 calculation, we of course have the mass of our sample.
01:49
And initially, if we're starting at a temperature of negative 91 .8, our pentane will be in its liquid state.
01:59
So we're going to write the specific key value of our, i guess, our n -pentine in liquid form.
02:07
So c, lick.
02:08
And our delta t will be equal to until the, i guess until our pentane boils minus our initial temperature.
02:24
So essentially we're going to have a liquid sample up until this boiling point.
02:31
And so doing this calculation, we get 28 times our specific heat in liquid form times our temperature.
02:47
Change.
02:47
So again, if we're going, i guess going up to our boiling point, our boiling point is 36 .2 degrees celsius.
02:56
So i'll be 36 .2 degrees celsius...