00:01
The reaction's enthalpy tells us whether a reaction absorbs or releases heat.
00:06
Now, the enthalpy is, if the enthalpy is positive, so entropy change is positive, this denotes that the reaction is endothermic, and so it absorbs heat from the surrounding.
00:18
If the entropy change is negative, then the reaction is exothermic.
00:23
That means it releases heat to its surroundings.
00:26
So consider a cold pack containing solar, sodium nitrate.
00:33
So when this cold pack is broken, the sodium nitrate dissolves in water.
00:40
And as a result, the temperature of the cold pack decreases.
00:44
So temperature decreases.
00:49
What we want to know is the sign of the delta h of the solution and also the delta s of the solution.
00:57
We have defined what delta h is.
01:00
Now let's discuss also what delta is...