Chemical Reactions and Stoichiometry - SS1 Chemistry Past Questions and Answers - page 2

Balancing chemical equations is the process of adjusting the coefficients in front of the chemical formulas to ensure that the number of atoms of each element is the same on both sides of the equation. A balanced equation accurately represents the stoichiometry, or the quantitative relationship, between the reactants and products in a chemical reaction.

 

The process of balancing chemical equations involves the following steps:

 

1. Identify the reactants and products in the chemical equation.
2. Count the number of atoms of each element on both sides of the equation.
3. Start by adjusting the coefficients of the compounds that contain the highest number of atoms of a particular element.
4. Use trial and error to modify the coefficients until the number of atoms is balanced on both sides of the equation.
5. Verify that the equation is balanced by counting the atoms of each element again.

 

Balanced equations are crucial for several reasons:

 

1. Conservation of mass: Balancing equations ensures that the law of conservation of mass is obeyed. According to this law, the total mass of the reactants must be equal to the total mass of the products. Balanced equations show that the same number and types of atoms are present before and after the reaction, preserving mass.

 

1. Stoichiometry: Balanced equations provide information about the mole-to-mole ratios between reactants and products. These ratios allow scientists to determine the amounts of substances involved in a reaction and predict the theoretical yield of products. It helps in understanding the quantitative aspects of a chemical reaction.

 

1. Predicting reaction outcomes: Balanced equations help predict the products and their quantities in a reaction. By knowing the stoichiometry, scientists can determine the limiting reactant, which is the reactant that is completely consumed, and the excess reactant. This information aids in understanding the efficiency and yield of reactions.