Why must the solutions to be mixed have to come to the same temperature?

Question

I was doing an experiment to find the stoichiometric ratio ( HCL/NaOH). I had to mix 3.0M of HCl with water, so the molarity would decrease to 1.0M and I had to wait for a few minutes until both of the solutions (HCL & water) came to the same temperature. Why was it important to wait until the solutions to be mixed had come to the same temperature?
Thank you!

Answer 1

If you are measuring volumes accurately (which you are in a titration), it is important that the densities are known accurately. If one solution is hotter than the other, its density will be different, and the volume measurements will not be as accurate as they should be.

Answer 2

It is most likely just for safety

The addition of ACID to water ( be a good boy and do like you auta: always add ACID TO THE WATER... never do the reverse )
gives off heat
Adding acid to alkalii also produces alot of heat so there is a chance of boiling the liquides

Hmmmm ... or evaporating some water and messing up your results!!!!