Writing and Reading Chemical Equations

This flashcard set covers the fundamentals of writing and reading chemical equations, including state symbols, reaction signs, and the properties of metals, nonmetals, and metalloids.

Chemical Equation

A written representation of a chemical reaction using symbols, formulas, and signs; often referred to as the chemists' shorthand for describing the sequence of a reaction.

Word Equation

A depiction of a chemical reaction using the names of the chemicals involved without chemical symbols or formulae.

Reactants

The substances involved in a reaction that are written on the left side of the equation.

Product

The result of a chemical reaction, written on the right side of the equation.

Yields ($\rightarrow$)

A symbol placed between reactants and products that indicates the direction of the reaction and represents the words produce, yield, or form.

Reversible Reaction ($\rightleftharpoons$)

A symbol used in place of a single arrow to indicate that a reaction can proceed in both directions.

$(s)$ (State Symbol)

Indicates that a reactant or product is in the solid state.

Precipitate ($\downarrow$)

An alternative symbol for solid state $(s)$, used specifically for a solid formed within a solution.

$(l)$ (State Symbol)

Indicates that a reactant or product is in the liquid state.

Aqueous Solution ($(aq)$)

Indicates that a reactant or product is dissolved in water.

$(g)$ (State Symbol)

Indicates that a reactant or product is in the gaseous state.

Gaseous Product ($\uparrow$)

An alternative symbol for gaseous state $(g)$, used only when the substance is a product of the reaction.

Catalyst

A substance used to alter the rate of a reaction, represented by its chemical formula (such as $MnO_2$) written above the yield arrow.

$\Delta$ (Heat)

A symbol placed over the reaction arrow to indicate that the reactants are being heated.

Pressure ($2\,atm$)

A symbol used to specify the exact pressure at which a reaction is carried out, such as $2\,atm$ or a general indication of pressure exceeding normal atmospheric levels.

Metals

Elements characterized as being shiny, good thermal and electrical conductors, having high density and melting points, and being solids at room temperature (except Mercury).

Nonmetals

Elements characterized as being dull, poor conductors, having low density and melting points, and possessing very high electronegativity.

Metalloids

Elements that have properties between metals and nonmetals, are solids at room temperature, and act as semiconductors.

Electronegativity (Metals vs. Nonmetals)

Measured as very low for metals and very high for nonmetals.

Plus Sign ($+$) in Word Equations

Read as "reacts with" or "and" when used between two reactants.

Coefficients

Numbers placed before chemical formulas in a chemical equation to ensure there are the same number of atoms on both the reactant and product sides.