The task in science lab: discover which solid substance, without tasting, is sugar. donna and dave have five substances to test, and unfortunately, two are white! "let's heat them! " suggested donna.

The answer to your question is: sugar melting point: 186°C

Explanation:

I think that Donna did an excellent suggestion. If we heat a substance till it melts, we are obtaining the melting point. This point is the temperature at which a solid changes from solid to liquid and is specific for every substance. That means that the melting point of sugar is different from the melting point of salt, etc. So, they could distinguish among the substance they have the one that is sugar.

For example:            sugar                  table salt      

Melting point            186°C                    801°C

qualitative observation deals with data that can be observed with our senses: sight, smell, touch, taste, and hearing. they do not involve measurements or numbers. for instance, colors, shapes, and textures of objects are all qualitative observations.