Acetic acid reacts with barium hydroxide. What is the sum of the coefficients for the reactants and products?
The correct answer and explanation is:
The balanced chemical equation for the reaction between acetic acid (CH₃COOH) and barium hydroxide (Ba(OH)₂) is:
2CH₃COOH+Ba(OH)₂→Ba(CH₃COO)₂+2H₂O2 \text{CH₃COOH} + \text{Ba(OH)₂} \rightarrow \text{Ba(CH₃COO)₂} + 2 \text{H₂O}
To determine the sum of the coefficients, we add the coefficients of the reactants and products:
- Reactants: 2 (CH₃COOH) + 1 (Ba(OH)₂) = 3
- Products: 1 (Ba(CH₃COO)₂) + 2 (H₂O) = 3
Therefore, the sum of the coefficients for the reactants and products is 3 + 3 = 6.
Explanation:
Acetic acid (CH₃COOH) is a weak acid, and barium hydroxide (Ba(OH)₂) is a strong base. When these two substances react, they undergo an acid-base neutralization reaction. In this reaction, the hydrogen ions (H⁺) from the acetic acid react with the hydroxide ions (OH⁻) from the barium hydroxide to form water (H₂O). The barium ions (Ba²⁺) combine with the acetate ions (CH₃COO⁻) from the acetic acid to form barium acetate (Ba(CH₃COO)₂), which is the salt produced in the reaction.
To balance the equation, we start with the barium hydroxide (Ba(OH)₂) because it has only one Ba²⁺ ion, and each acetate ion (CH₃COO⁻) has a negative charge. Two acetic acid molecules are needed to provide the two acetate ions that will balance the barium ion’s charge.
The final balanced equation shows that for every two molecules of acetic acid, one molecule of barium hydroxide reacts, producing one molecule of barium acetate and two molecules of water.
The sum of the coefficients reflects the stoichiometry of the reaction, which ensures that the number of atoms of each element is the same on both sides of the equation.