What is a Chemical Equation?

Multiple Choice

Which of the following best describes the role of a chemical equation?

• It describes a chemical change by showing reactants and products.

• It lists all the elements in the periodic table.

• It measures the temperature of a reaction.

• It shows the physical state of substances only.

Multiple Choice

What is the difference between a reactant and a product in a chemical reaction?

• Reactants are the chemicals you end with, products are what you start with

• Reactants are always gases, products are always solids

• Reactants are the chemicals you start with, products are the new chemicals formed

• Reactants and products are always the same

Open Ended

Explain how subscripts and coefficients are used in chemical equations to represent the number of atoms and molecules.

Multiple Choice

In the chemical equation 2H₂ + O₂ → 2H₂O, identify the reactants and the product.

• Reactants: H₂O, Product: H₂ and O₂

• Reactants: H₂ and O₂, Product: H₂O

• Reactants: O₂ and H₂O, Product: H₂

• Reactants: H₂, Product: O₂ and H₂O

Fill in the Blank

The Law of Conservation of Mass states that matter is neither ___ nor destroyed in a chemical reaction.

Multiple Choice

Which of the following statements best explains why the equation CH₄ + O₂ → CO₂ + H₂O is unbalanced?

• There are more carbon atoms on the product side than the reactant side.

• The number of hydrogen and oxygen atoms are not the same on both sides.

• There are more molecules on the reactant side than the product side.

• The equation has the same number of each type of atom on both sides.

Multiple Select

Based on the diagrams of the unbalanced and balanced equations, what must be true for a chemical equation to be considered balanced? Select all that apply.

• The number of each type of atom must be the same on both sides of the equation.

• The total number of molecules must be the same on both sides.

• The types of atoms must be the same on both sides of the equation.

• The equation must follow the Law of Conservation of Mass.

Multiple Choice

Which of the following is NOT a rule for balancing chemical equations according to the 'Rules of the Game'?

• You can change subscripts to balance the equation.

• Matter cannot be created or destroyed.

• You can ONLY CHANGE coefficients.

• Coefficients can only go in front of chemical formulas.

Fill in the Blank

In the balanced equation N2 + 3H2 → ___NH3, what number goes in the blank?

Multiple Select

Based on the examples shown, which steps are helpful when balancing chemical equations?

• Treating polyatomic ions as one unit if they appear on both sides of the equation

• Changing subscripts to balance atoms

• Balancing big formulas first and saving free elements for last

• Placing coefficients in the middle of formulas

Multiple Choice

What are the main parts of a chemical equation?

• Reactant and Product

• Element and Compound

• Acid and Base

• Metal and Nonmetal