Physical Science Final Exam Review III

A certain atom has 12 protons, 10 electrons, and 13 neutrons. It is a __________ atom.

• manganese

• sodium

• neon

• magnesium

What is the total number of atoms in the compound Ca(ClO₃)₂?

• 9

• 5

• 3

• 2

Why do the noble gases NOT form compounds readily?

• They have empty outer energy levels.

• Their outer energy levels are completely filled with electrons.

• They have seven electrons in the outer energy levels.

• They have no electrons.

Each molecule of hydrochloric acid, HCl, contains one atom of hydrogen and

• one atom of oxygen.

• two atoms of oxygen.

• one atom of chlorine.

• two atoms of chlorine.

How many electrons are needed in the outer energy levels of most atoms for the atom to be chemically stable?

• 2

• 8

• 6

• 4

The elements that make up a compound and the exact number of atoms of each element in a unit of the compound can be shown in a ____.

• chemical formula

• chemical symbol

• subscript

• superscript

A substance that cannot be broken down into simpler substances is

• a compound.

• an element.

• a mixture.

• an atom.

A material that can be represented by a chemical formula is

• an element.

• a mixture.

• a compound.

• a homogeneous solution.

Matter is defined as anything that

• has mass and takes up space.

• can be weighed.

• can be seen and touched.

• contains kinetic or potential energy.

A substance that is made of atoms of more than one type bound together in a chemical bond is called a ________.

• solution

• heterogenous mixture

• compound

• homogenous mixture