Question

Use the chemical equation to answer the question.

2HCl(aq) + Zn(s) → ZnCl2(aq) + H2(g)

The molar mass of hydrogen (H) is 1 g/mol, the molar mass of chlorine (Cl) is 35 g/mol, and the molar mass of zinc (Zn) is 65 g/mol. When 130 grams of zinc react completely in hydrochloric acid (HCl), how much is the total mass of the products?

(1 point)
Responses

144 g
144 g

130 g
130 g

270 g
270 g

274 g

Answer 1

To find the total mass of the products when 130 grams of zinc react completely with hydrochloric acid, we can start by determining how many moles of zinc are present and then how much mass of products is produced.

1. **Calculate the moles of zinc (Zn):**
\[
\text{Moles of Zn} = \frac{\text{mass of Zn}}{\text{molar mass of Zn}} = \frac{130 \text{ g}}{65 \text{ g/mol}} = 2 \text{ moles of Zn}
\]

2. **Use the balanced chemical equation:**
\[
2 \text{HCl} (aq) + \text{Zn} (s) \rightarrow \text{ZnCl}_2 (aq) + \text{H}_2 (g)
\]
According to the balanced equation:
- 2 moles of HCl react with 1 mole of zinc to produce 1 mole of zinc chloride (ZnCl2) and 1 mole of hydrogen gas (H2).

3. **Determine the products formed:**
From 2 moles of Zn, we will produce:
- 2 moles of ZnCl2
- 2 moles of H2 (since 1 mole of Zn produces 1 mole of H2)

4. **Calculate the mass of the products:**
- **Mass of ZnCl2:**
\[
\text{Molar mass of ZnCl2} = 65 \text{ g/mol (Zn)} + 2 \times 35 \text{ g/mol (Cl)} = 65 + 70 = 135 \text{ g/mol}
\]
\[
\text{Mass of 2 moles of ZnCl2} = 2 \text{ moles} \times 135 \text{ g/mol} = 270 \text{ g}
\]

- **Mass of H2:**
\[
\text{Molar mass of H2} = 2 \times 1 \text{ g/mol} = 2 \text{ g/mol}
\]
\[
\text{Mass of 2 moles of H2} = 2 \text{ moles} \times 2 \text{ g/mol} = 4 \text{ g}
\]

5. **Total mass of products:**
\[
\text{Total mass of products} = \text{Mass of ZnCl2} + \text{Mass of H2} = 270 \text{ g} + 4 \text{ g} = 274 \text{ g}
\]

So, the total mass of the products when 130 grams of zinc react completely in hydrochloric acid is **274 g**.