Question

one student claims that the meaning of this balanced equation is \2 grams of h₂ reacts with 1 gram of o₂ to form 2 grams of h₂o\ do you agree or disagree? explain how the coefficients of the equations are supposed to be used. frq 2 predict the products of the following double replacement reaction. fill in the blanks hcl + naoh → ____ + __ frq 3 balance the chemical equation. explain the process and importance of balancing the equation. __cacl₂ + __pb(no₃)₂ → __ca(no₃)₂ + ____pbcl₂

Explanation:

First Question (Agree/Disagree on Equation Interpretation)

I disagree. The coefficients in a balanced chemical equation represent mole ratios (or particle ratios), not mass ratios. For the water formation reaction ($2\text{H}_2 + \text{O}_2
ightarrow 2\text{H}_2\text{O}$), 2 moles of $\text{H}_2$ (4 grams) reacts with 1 mole of $\text{O}_2$ (32 grams) to form 2 moles of $\text{H}_2\text{O}$ (36 grams). Coefficients scale the relative amounts of reactants and products in terms of moles, not grams.

In a double replacement reaction, the cations ($\text{H}^+$ and $\text{Na}^+$) and anions ($\text{Cl}^-$ and $\text{OH}^-$) swap partners. $\text{H}^+$ combines with $\text{OH}^-$ to form water, and $\text{Na}^+$ combines with $\text{Cl}^-$ to form sodium chloride.

Step1: Count atoms on reactant side

Ca: 1, Cl: 2, Pb: 1, N: 2, O: 6

Step2: Count atoms on product side

Ca: 1, N: 2, O: 6, Pb: 1, Cl: 2

Step3: Verify equal atom counts

All elements have matching atom counts on both sides, so the equation is already balanced with coefficients of 1 for all species.

Step4: Explain balancing process

1. Identify all elements in the reaction.
2. Count the number of each atom on reactant and product sides.
3. Add coefficients to equalize atom counts for all elements (no changes needed here).

Step5: Explain balancing importance

Balancing ensures the law of conservation of mass is obeyed: no atoms are created or destroyed in a chemical reaction, so the total mass of reactants equals the total mass of products. It also gives the correct mole ratios for reactants and products.

Answer:

Disagree. Coefficients represent mole/particle ratios, not mass ratios. The correct mass relationship is 4 g $\text{H}_2$ reacts with 32 g $\text{O}_2$ to form 36 g $\text{H}_2\text{O}$.

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FRQ 2 (Double Replacement Reaction)