Problems... Quiz

1. Classify the following as either a chemical or physical change.
Burning wood.... CHEMICAL
Crushing a rock .... PHYSICAL
Dissolving sugar in water .... PHYSICAL
The rusting of iron .... CHEMICAL
2. Classify the following as to whether or not they are pure substances or mixtures.
milk .... MIXTURE
table salt .... PURE.... wrong, mixture
sugar .... MIXTURE... wrong, pure
steel .... PURE... wrong, mixture
3. A cup of black coffee is considered to be __?__ and a/an __?__ substance.
(b) homogeneous…..impure
4. The boiling of water is considered to be a __?__ change and the temperature at which water boils is considered to be a __?__ property.
(d) physical…..physical