Question

Assuming no evaporation , what error is introduced if the water is warmed after being delivered into the flask but prior to weighing? Explain.

Answer 1

By just warming water, assuming no evaporation will not cause any mass change (assuming no or negligible dissolved gases).
But it could change the same things:-
1. Could cause precipitation of salts (exp. CaCO3) present in it when it is cooled down.

2. Change in concentration of salts dissolved in water could alter the melting and boiling point.

3. Now its temperature is elevated molecules of water are moving colliding at a much faster speed, thus H-bondings are weaker or we could say less effective causing some decrease in its viscosity.

4. Refractive index could also change to some extent.

5. Less no of H-bonds that means less attraction between molecules can cause increase in volume but that will be very small change.