O

Doesn't form well with other compounds/ elements, last column on the periodic table

One half of the distance from distance from center of two like atoms

Water

The mass in grams of one mole of a given substance

Li

Harder, denser, stronger, and have higher melting points than the alkali metals

The periodic table contains ____ and _____ trends

Sodium chloride

6.022x10^23 the number of particles in a mole

Na

Elements that combine with most metals to form salts and that belong to Group 17 of the periodic table

The amount of energy needed to remove an electron from a specific atom or ion in its ground state in the gas phase

Carbon dioxide

The fundamental SI unit used to measure the amount of a substance

K

Elements that represent the entire range of chemical properties and belong to Groups 1, 2, and 13-18 in the periodic table

An atom or group of atoms that has gained or lost one or more electrons to acquire a net electric charge

CO

The mass of an atom in atomic mass units

Ba

Highly reactive metallic elements which form alkaline solutions in water, burn in air, and belong to. Group 1 of the periodic table

Atomic size decreases from ___ to ___ across a period

CH4

Properties of elements tend to change with increasing atomic number in a periodic way