Elements, Periodic Table, Atoms

With the exception of helium, Group 18 elements usually have ______________ valence electrons, so they do not usually react with other elements.

• 0
• 1
• 8
• 7

In the periodic table, atoms are arranged from left to right and from top to bottom in order of increasing

• atomic mass.
• atomic number.
• electrons.
• isotopes.

The smallest particle into which an element can be divided and still be the same substance is a(n)

• atom.
• ion.
• alloy.
• isotope.

The electrons in the outermost energy level of an atom are

• ions.
• isotopes.
• periods.
• valence electrons.

The "salt-producing" family of nonmetals are known as

• noble gases.
• halogens.
• carbons.
• alkali earth metals.

The modern periodic table is organized according to atomic mass.

• True
• False

The horizontal rows in the periodic table are known as groups.

• True
• False

The most chemically reactive metals are in Group 1 of the periodic table.

• True
• False

Nonmetals can be found on the left side of the periodic table.

• True
• False

An electrically charged particle is called an ion.

• True
• False