Question

question 7
the law of constant composition applies to
a heterogeneous mixtures
b metalloids
c compounds
d homogeneous mixtures
e metals

Explanation:

The law of constant composition (also known as the law of definite proportions) states that a given chemical compound always contains its component elements in fixed ratio (by mass) and does not depend on its source or method of preparation. Compounds are substances composed of two or more elements chemically combined in a fixed proportion. Mixtures (both homogeneous and heterogeneous) do not have a fixed composition. Metals and metalloids are elements, not substances with a fixed - proportion composition in the sense of the law of constant composition.

Answer:

C. compounds