Writing and Balancing Equations

Write the chemical equation for the reaction: Solid iron + solid sulfur → solid iron (II) sulfide.

• Fe(s) + S(s) → FeS(s)

• Fe(s) + S(s) → Fe2S3(s)

• Fe(s) + S(s) → FeS2(s)

• Fe(s) + S(s) → Fe3S4(s)

How many oxygen atoms are in the compound (OH)₂?

• 1 oxygen atom

• 2 oxygen atoms

• 3 oxygen atoms

• 4 oxygen atoms

What is a balanced equation?

• A balanced equation has different numbers of atoms on each side of the equation.

• A balanced equation has the same number of each type of atom on both sides of the equation, indicating that mass is conserved during a chemical reaction.

• A balanced equation is one that has no reactants or products.

• A balanced equation is only applicable to physical changes, not chemical reactions.

What does the coefficient in a chemical equation represent?

• The coefficient indicates the number of molecules or moles of a substance involved in the reaction.

• The coefficient represents the temperature at which the reaction occurs.

• The coefficient shows the pressure of the gas involved in the reaction.

• The coefficient indicates the color change of the substances during the reaction.

What is a word equation?

• A mathematical representation of a chemical reaction.

• A way of representing a chemical reaction using the names of the reactants and products.

• A graphical representation of chemical compounds.

• A formula that shows the quantities of reactants and products.

How do you determine if a chemical equation is balanced?

• Count the number of atoms of each element on both sides of the equation. If they are equal, the equation is balanced.

• Check if the coefficients of the reactants and products are the same.

• Ensure that the total mass of the reactants equals the total mass of the products without counting atoms.

• Look for equal numbers of molecules on both sides of the equation.

What is the law of conservation of mass?

• The law states that mass is neither created nor destroyed in a chemical reaction; the total mass of reactants equals the total mass of products.

• Mass can be created or destroyed in a chemical reaction.

• The total mass of products is always greater than the total mass of reactants.

• Mass is only conserved in physical changes, not in chemical reactions.