Chemistry worksheet for converting word equations into balanced chemical equations.

Let's solve each of these word equations by converting them into balanced chemical equations. I'll go step-by-step for each one.

---

1. zinc + lead(II) nitrate → zinc nitrate + lead

Step 1: Write formulas
- Zinc = Zn
- Lead(II) nitrate = Pb(NO₃)₂ (Pb²⁺ and NO₃⁻)
- Zinc nitrate = Zn(NO₃)₂
- Lead = Pb

Unbalanced equation:
Zn + Pb(NO₃)₂ → Zn(NO₃)₂ + Pb

Balance:
All atoms are already balanced (1 Zn, 1 Pb, 2 NO₃ on each side).

✔ Balanced Equation:
$$
\text{Zn} + \text{Pb(NO}_3)_2 \rightarrow \text{Zn(NO}_3)_2 + \text{Pb}
$$

---

2. aluminum bromide + chlorine → aluminum chloride + bromine

Formulas:
- Aluminum bromide = AlBr₃
- Chlorine = Cl₂ (diatomic)
- Aluminum chloride = AlCl₃
- Bromine = Br₂ (diatomic)

Unbalanced:
AlBr₃ + Cl₂ → AlCl₃ + Br₂

Balance:
- Al: 1 on both sides ✔
- Br: 3 on left, 2 on right → LCM of 3 and 2 is 6 → use 2 AlBr₃ and 3 Br₂
- Cl: 2 on left, 3 on right → need 6 Cl → use 3 Cl₂

So:
2 AlBr₃ + 3 Cl₂ → 2 AlCl₃ + 3 Br₂

Check:
- Al: 2 = 2 ✔
- Br: 6 = 6 ✔
- Cl: 6 = 6 ✔

✔ Balanced Equation:
$$
2\text{AlBr}_3 + 3\text{Cl}_2 \rightarrow 2\text{AlCl}_3 + 3\text{Br}_2
$$

---

3. sodium phosphate + calcium chloride → calcium phosphate + sodium chloride

Formulas:
- Sodium phosphate = Na₃PO₄
- Calcium chloride = CaCl₂
- Calcium phosphate = Ca₃(PO₄)₂
- Sodium chloride = NaCl

Unbalanced:
Na₃PO₄ + CaCl₂ → Ca₃(PO₄)₂ + NaCl

Balance:
- PO₄: 1 on left, 2 on right → use 2 Na₃PO₄
- Ca: 1 on left, 3 on right → use 3 CaCl₂
- Na: 6 on left → need 6 NaCl
- Cl: 6 on left → 6 on right → OK

So:
2 Na₃PO₄ + 3 CaCl₂ → Ca₃(PO₄)₂ + 6 NaCl

✔ Balanced Equation:
$$
2\text{Na}_3\text{PO}_4 + 3\text{CaCl}_2 \rightarrow \text{Ca}_3(\text{PO}_4)_2 + 6\text{NaCl}
$$

---

4. potassium chlorate when heated → potassium chloride + oxygen gas

Formulas:
- Potassium chlorate = KClO₃
- Potassium chloride = KCl
- Oxygen gas = O₂

Unbalanced:
KClO₃ → KCl + O₂

Balance:
- K: 1 = 1 ✔
- Cl: 1 = 1 ✔
- O: 3 on left, 2 on right → LCM of 3 and 2 is 6 → use 2 KClO₃ and 3 O₂

But then:
2 KClO₃ → 2 KCl + 3 O₂

Check:
- K: 2 = 2 ✔
- Cl: 2 = 2 ✔
- O: 6 = 6 ✔

✔ Balanced Equation:
$$
2\text{KClO}_3 \xrightarrow{\Delta} 2\text{KCl} + 3\text{O}_2
$$
*(Δ means heat)*

---

5. aluminum + hydrochloric acid → aluminum chloride + hydrogen gas

Formulas:
- Aluminum = Al
- Hydrochloric acid = HCl
- Aluminum chloride = AlCl₃
- Hydrogen gas = H₂

Unbalanced:
Al + HCl → AlCl₃ + H₂

Balance:
- Al: 1 = 1 ✔
- Cl: 1 on left, 3 on right → use 3 HCl
- H: 3 on left, 2 on right → LCM of 3 and 2 is 6 → use 6 HCl and 3 H₂

So:
2 Al + 6 HCl → 2 AlCl₃ + 3 H₂

Check:
- Al: 2 = 2 ✔
- H: 6 = 6 ✔
- Cl: 6 = 6 ✔

✔ Balanced Equation:
$$
2\text{Al} + 6\text{HCl} \rightarrow 2\text{AlCl}_3 + 3\text{H}_2
$$

---

6. calcium hydroxide + phosphoric acid → calcium phosphate + water

Formulas:
- Calcium hydroxide = Ca(OH)₂
- Phosphoric acid = H₃PO₄
- Calcium phosphate = Ca₃(PO₄)₂
- Water = H₂O

Unbalanced:
Ca(OH)₂ + H₃PO₄ → Ca₃(PO₄)₂ + H₂O

Balance:
- Ca: 1 on left, 3 on right → use 3 Ca(OH)₂
- PO₄: 1 on left, 2 on right → use 2 H₃PO₄
- H: from 3×2 = 6 H in OH and 2×3 = 6 H in H₃PO₄ → total 12 H on left
- O: many, but let’s count H₂O
- H: 12 on left → must make 6 H₂O (since each has 2 H)

So:
3 Ca(OH)₂ + 2 H₃PO₄ → Ca₃(PO₄)₂ + 6 H₂O

Check:
- Ca: 3 = 3 ✔
- P: 2 = 2 ✔
- O: Left: 3×2 = 6 from OH, 2×4 = 8 from PO₄ → 14; Right: 8 from PO₄ + 6 from H₂O = 14 ✔
- H: 3×2 + 2×3 = 6+6=12; Right: 6×2=12 ✔

✔ Balanced Equation:
$$
3\text{Ca(OH)}_2 + 2\text{H}_3\text{PO}_4 \rightarrow \text{Ca}_3(\text{PO}_4)_2 + 6\text{H}_2\text{O}
$$

---

7. copper + sulfuric acid → copper(II) sulfate + water + sulfur dioxide

Note: This is a redox reaction involving concentrated H₂SO₄ and Cu.

Formulas:
- Copper = Cu
- Sulfuric acid = H₂SO₄
- Copper(II) sulfate = CuSO₄
- Water = H₂O
- Sulfur dioxide = SO₂

Unbalanced:
Cu + H₂SO₄ → CuSO₄ + H₂O + SO₂

Balance:
This is not a simple displacement. It's a redox reaction where H₂SO₄ is reduced to SO₂ and Cu is oxidized to Cu²⁺.

Standard reaction:
Cu + 2 H₂SO₄ → CuSO₄ + SO₂ + 2 H₂O

Check:
- Cu: 1 = 1 ✔
- S: 2 on left → 1 in CuSO₄, 1 in SO₂ → 2 ✔
- H: 4 on left → 4 in 2 H₂O ✔
- O: 8 on left → 4 in CuSO₄, 2 in SO₂, 2 in 2 H₂O → 8 ✔

✔ Balanced Equation:
$$
\text{Cu} + 2\text{H}_2\text{SO}_4 \rightarrow \text{CuSO}_4 + \text{SO}_2 + 2\text{H}_2\text{O}
$$

---

8. hydrogen + nitrogen monoxide → water + nitrogen

Formulas:
- Hydrogen = H₂
- Nitrogen monoxide = NO
- Water = H₂O
- Nitrogen = N₂ (diatomic)

Unbalanced:
H₂ + NO → H₂O + N₂

Balance:
- N: 1 on left, 2 on right → use 2 NO
- O: 2 on left → need 2 H₂O
- H: 2 on left → 4 H needed → use 2 H₂

So:
2 H₂ + 2 NO → 2 H₂O + N₂

Check:
- H: 4 = 4 ✔
- N: 2 = 2 ✔
- O: 2 = 2 ✔

✔ Balanced Equation:
$$
2\text{H}_2 + 2\text{NO} \rightarrow 2\text{H}_2\text{O} + \text{N}_2
$$

---

✔ Final Answers:

1. $ \text{Zn} + \text{Pb(NO}_3)_2 \rightarrow \text{Zn(NO}_3)_2 + \text{Pb} $

2. $ 2\text{AlBr}_3 + 3\text{Cl}_2 \rightarrow 2\text{AlCl}_3 + 3\text{Br}_2 $

3. $ 2\text{Na}_3\text{PO}_4 + 3\text{CaCl}_2 \rightarrow \text{Ca}_3(\text{PO}_4)_2 + 6\text{NaCl} $

4. $ 2\text{KClO}_3 \xrightarrow{\Delta} 2\text{KCl} + 3\text{O}_2 $

5. $ 2\text{Al} + 6\text{HCl} \rightarrow 2\text{AlCl}_3 + 3\text{H}_2 $

6. $ 3\text{Ca(OH)}_2 + 2\text{H}_3\text{PO}_4 \rightarrow \text{Ca}_3(\text{PO}_4)_2 + 6\text{H}_2\text{O} $

7. $ \text{Cu} + 2\text{H}_2\text{SO}_4 \rightarrow \text{CuSO}_4 + \text{SO}_2 + 2\text{H}_2\text{O} $

8. $ 2\text{H}_2 + 2\text{NO} \rightarrow 2\text{H}_2\text{O} + \text{N}_2 $

---

Let me know if you'd like these with states (s, l, g, aq)!