Technician A and Technician B are examining the same substance. Technician A records the mass, volume, and weight of the substance and decides that it is sugar. Technician B records the melting point, density, and boiling point of the substance and decides that it is salt. Which technician’s answer is more apt to be correct and why?

2 answers

I'd go with the one who actually tasted his substance.
Say you have two gallons of water in one bucket and one gallon in another. They would weigh different, the volume is different (1 gallon vs 2), and the mass would differ. However, they are the same substance.

However, if you boiled the water in these buckets, they would both boil around 100C.

With that in mind, which property would you trust more to identify a substance such as water?