Balancing Chemical Equations Review

Front

What is a coefficient in a chemical equation?

Back

A coefficient is a number placed in front of a chemical formula to indicate how many molecules or moles of that substance are involved in the reaction.

Front

What does the principle of conservation of mass state?

Back

The principle of conservation of mass states that matter is not created or destroyed in a chemical reaction; the total mass of the reactants equals the total mass of the products.

Front

How many atoms of aluminum are in the equation: 4Al + 3O₂ --> 2Al₂O₃?

Back

There are 4 atoms of aluminum on each side of the equation.

Front

Balance the equation: N₂ + H₂ --> NH₃.

Back

The balanced equation is: 1N₂ + 3H₂ --> 2NH₃.

Front

How many phosphorus atoms are in PO₄?

Back

There is 1 phosphorus atom in PO₄.

Front

What is a product in a chemical reaction?

Back

A product is a substance that is formed as a result of a chemical reaction.

Front

What is a reactant in a chemical reaction?

Back

A reactant is a substance that undergoes change during a chemical reaction.

Front

What does it mean to balance a chemical equation?

Back

Balancing a chemical equation means ensuring that the number of atoms of each element is the same on both sides of the equation.

Front

What is a subscript in a chemical formula?

Back

A subscript is a number written below and to the right of a chemical symbol that indicates the number of atoms of that element in a molecule.

Front

What is the significance of the arrow in a chemical equation?

Back

The arrow in a chemical equation indicates the direction of the reaction, showing that reactants are transformed into products.