9B Science: Balancing Chemical Equations

__CaO + __H₂O → __Ca(OH)₂

balanced

__Na + __F₂ → __NaF

2, 1, 2

__Na + __MgF₂ → __NaF + __Mg

2, 1, 2, 1

__BaCl₂ + __Na₂SO₄ → __NaCl + __BaSO₄

1, 1, 2, 1

__Sn + __HF → __SnF₂ + __H₂

1, 2, 1, 1

__Fe +__O₂ → __Fe₂O₃

4, 3, 2

__CS₂ + __O₂ → __CO₂ + __SO₂

1, 3, 1, 2

__MgS + __O₂ → __MgO + __SO₂

2, 3, 2, 2

Complete combustion of methane gas.

__CH₄ + __O₂ → __CO₂ + __H₂O

1,2,1,2

A chemical substance that is present at the start of a chemical reaction.

reactant

A chemical substance formed as a result of a chemical reaction

product

A representation of a chemical reaction that uses symbols to show the relationship between the reactants and the products

chemical equation

A process during which chemical bonds between atoms are broken and new ones are formed. Producing one or more different substances.

chemical reaction

Makes, creates, produces; Arrow in chemical equation

yields

During any chemical reaction, the mass of the products is always equal to the mass of the reactants

law of conservation of mass

A number in front of a chemical formula in an equation that indicates how many molecules or atoms of each reactant and product are involved in a reaction.

coefficient

A number written slightly below and to the right of a chemical symbol that shows how many atoms of an element are in a compound.

subscript

keep mass of products and reactants the same by adjusting coefficients as necessary

balancing chemical equations