Chapter 3- Stoichiochemistry

Sodium symbol

Na

Sodium hydroxide formula

NaOH

Molecular formula

The actual number of atoms of each element present in a compound.

Compound with 3 carbon atoms and 8 hydrogen atoms

C3H8

Formula of the compound shown in the flashcard

C2H4Br2

State symbols

(g) gas, (aq) aqueous, (l) liquid, (s) solid

Examples of gases at room temperature

Cl2, F2, N2, H2, O2, and the noble gases.

Examples of aqueous substances

Any substance dissolved in water, e.g. NaCl(aq), H2SO4(aq), KOH(aq).

Examples of liquids at room temperature

H2O(l), Br2(l), Hg(l).

Examples of solids at room temperature

Most metals such as Na(s), Mg(s), Fe(s), and I2(s).

Hydrochloric acid + sodium hydroxide equation

HCl(aq) + NaOH(aq) → NaCl(aq) + H2O(l)

Hydrogen + chlorine equation

H2(g) + Cl2(g) → 2HCl(g)

Empirical formula

The smallest whole

Empirical formula of Fe2O4

FeO2

Formula of sodium oxide (Na+ and O2−)

Na2O

Formula of magnesium hydroxide (Mg2+ and OH−)

Mg(OH)2

Diatomic molecules

Molecules containing two atoms per molecule. Examples: H2, N2, O2, F2, Cl2, Br2, I2.

Ionic equation

An equation that shows only the ions that take part in a reaction.

Ionic equation for nitric acid and sodium hydroxide

H+(aq) + OH−(aq) → H2O(l)

Ionic equation for silver nitrate and sodium chloride

Ag+(aq) + Cl−(aq) → AgCl(s)