An Atom That Has an Atomic Number of 20 and a Mass

question 9

Multiple Choice

An atom that has an atomic number of 20 and a mass number of 42 is an isotope of an atom that has:

• A)an atomic number of 21 and a mass number of 42
• B)an atomic number of 20 and a mass number of 40
• C)22 neutrons and 20 protons
• D)22 protons and 20 neutrons

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Definitions:

Magma

Molten rock, which may or may not contain some crystals, solidified rock, and gas.

Hydrothermal Rock

Rock formed from the alteration of pre-existing rock by mineral-rich hot water.

Sedimentary Rock

Rock resulting from the consolidation of sediment.

Igneous Rock

A type of rock that forms from the cooling and solidification of magma or lava.