Bromine, a liquid at room temperature, has a boiling point of 58°c and a melting point of –7.2°c. bromine can be classified as a

Explanation:

A pure substance is defined as the substance that contains same type of atoms or atoms of one type of molecule.

A pure substance will always have a fixed melting and boiling point.

For example, at room temperature bromine is a liquid and its boiling point of and a melting point of .

Hence, bromine is a pure substance.

Whereas when two or more different substances are mixed together irrespective of their ratio by mass then they are known as mixtures. And, mixtures always show a range of temperature for their melting and boiling point.

Hence, bromine is not a mixture.

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the number of valence electrons for each molecule or ion is shown beneath the structure. remember hydrogen will not have more than two electrons. this hydrogen is part of a covalent bond (sharing two electrons). a double bond here would cause hydrogen to share four electrons with phosphorus.