Question

Chemical Equations Vocabulary
Chemical Reaction


Reactants

Products

Chemical Equation


Coefficient


Subscript


Synthesis Reaction


Combustion Reaction


Decomposition Reaction
Single Replacement Reaction


Double replacement reaction


Precipitate


Aqueous Solution


Solutes


Solvent


Complete Ionic Equation


Spectator ions

Net Ionic Equations

Answer 1

Here are clear, concise definitions and simple examples for each term, plus a short how-to for writing complete ionic and net ionic equations.

- Chemical Reaction
A process where substances (reactants) change into new substances (products) by breaking and forming chemical bonds. Example: 2 H2 + O2 → 2 H2O

- Reactants
The starting substances in a chemical reaction (left side of the equation). In 2 H2 + O2 → 2 H2O, reactants are H2 and O2.

- Products
The substances formed by a chemical reaction (right side of the equation). In 2 H2 + O2 → 2 H2O, the product is H2O.

- Chemical Equation
A symbolic representation of a chemical reaction using formulas and symbols (→, +, coefficients, state symbols). Example: CH4 + 2 O2 → CO2 + 2 H2O

- Coefficient
A whole number placed in front of a formula in a chemical equation that indicates relative amounts (moles or molecules). In 2 H2O, the 2 is a coefficient.

- Subscript
A small number written in a chemical formula that indicates how many atoms of an element are in one molecule. In H2O, the 2 (subscript) means two H atoms per molecule.

- Synthesis Reaction (Combination)
Two or more reactants combine to form a single product. General: A + B → AB. Example: 2 Na + Cl2 → 2 NaCl

- Combustion Reaction
A substance (often a hydrocarbon) reacts with O2 to produce CO2 and H2O (if complete combustion). Example: CH4 + 2 O2 → CO2 + 2 H2O

- Decomposition Reaction
A single compound breaks down into two or more simpler substances. General: AB → A + B. Example: 2 H2O2 → 2 H2O + O2

- Single Replacement (Single Displacement) Reaction
One element replaces another in a compound. General: A + BC → AC + B. Example: Zn + 2 HCl → ZnCl2 + H2

- Double Replacement (Double Displacement) Reaction
Exchange of ions between two compounds to form two new compounds. General: AB + CD → AD + CB. Example: AgNO3 + NaCl → AgCl + NaNO3

- Precipitate
An insoluble solid formed in a reaction in solution. Marked as (s) in equations. Example: AgCl(s) formed from Ag+ and Cl- in aqueous solution.

- Aqueous Solution
A solution where water is the solvent; indicated by (aq). Example: NaCl(aq) is salt dissolved in water.

- Solute
The substance dissolved in a solvent (smaller amount). In saltwater, NaCl is the solute.

- Solvent
The medium that dissolves the solute (larger amount). In aqueous solutions, water is the solvent.

- Complete Ionic Equation
An equation that shows all strong electrolytes (soluble ionic compounds, strong acids/bases) as separate ions. Keep solids, liquids, gases intact. Example from AgNO3(aq) + NaCl(aq) → AgCl(s) + NaNO3(aq):
Complete ionic: Ag+ + NO3- + Na+ + Cl- → AgCl(s) + Na+ + NO3-

- Spectator Ions
Ions that appear unchanged on both sides of the complete ionic equation; they do not participate in the reaction. In the AgCl example, Na+ and NO3- are spectators.

- Net Ionic Equation
The equation that remains after removing spectator ions from the complete ionic equation; shows only the species that actually change. For AgNO3 + NaCl → AgCl + NaNO3:
Net ionic: Ag+ + Cl- → AgCl(s)

Quick rules for writing complete ionic and net ionic equations:
- Write the balanced molecular equation with state symbols (s, l, g, aq).
- Split all strong electrolytes (soluble ionic compounds, strong acids/bases) into their ions for the complete ionic equation; leave solids, liquids, and gases undissociated.
- Cancel identical ions on both sides (spectators) to get the net ionic equation.
- Make sure the net ionic equation is charge- and mass-balanced.

If you want, I can provide more examples or practice problems for any of the reaction types or ionic equations.