Answer:
B. A mixture has different properties throughout; a pure substance has the same properties throughout
Step-by-step explanation:
We have two classes of substances which are pure and impure substances.
Pure substances are elements and compounds
Impure substance are simply mixtures.
Mixtures have the following properties;
- Their composition is indefinite i.e. they consist of two or more elements and or compounds in any proportion by mass.
- Constituents retain their identities i.e. physical properties are retained.
- Constituents react differently to changed conditions
- They can easily be separated by physical methods.