Which Is Not a Single Pure Substance

question 72

Multiple Choice

Which is not a single pure substance?

• A)copper
• B)water
• C)brass
• D)chlorine

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Definitions:

Isotope

Variants of an element that contain the same number of protons but different numbers of neutrons in their nuclei.

Neutrons

Subatomic particles, found in the nucleus of an atom, that have no electrical charge and a mass slightly larger than that of protons.

Element

A substance that cannot be broken down into simpler substances by chemical means and is made up of atoms all with the same number of protons.

Isotope

Variants of a particular chemical element which differ in neutron number, and consequently in mass, but not in electrical charge.