Heat of mixing [Lecture]

[@giftsadique1806]

Why used 25°C as the starting temperature for both NAOH and H2O. How did you come with that 25°C prof?

[@kgharding29]

The value of the heat of mixing in this example was given at 25degC (possibly not made clear enough in the video), and as such the basis of each of NaOH and H2O was taken from the same point. The way the question is solved, you should note that if you had taken a different starting temperature (basis) for the individual chemicals, then heated to 25degC, the maths cancels out in such a way that this would not have made a difference to the final answer.