Question

When comparing melting temperature ranges of pure and impure samples, which of the following statements describes the melting temperature range of an impure sample?For a pure substance: the melting temperature range is narrower than that of an impure sample or the melting temperature range is broader than that of an impure sample?

For an impure substance: the melting point is higher than that of a pure samplr or the melting point is lower than that of a pure sample

Answer 1

Addition of impurity results in lowering of the melting point, thus increases the melting point range. The pure substances have the higher melting points and thus decreases the melting point range.

So following are the correct sentences.

For a pure substance, the melting temperature range is narrower than that of an impure sample.

For an impure substance, the melting point is lower than that of a pure sample.