Chemistry Worksheet: Easy Balancing Equations Problems by Ray Byle - Free Printable

The task involves balancing chemical equations. Balancing a chemical equation means ensuring that the number of atoms of each element is the same on both sides of the equation (reactants and products). Here's how to solve each equation step by step:

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1. 2C + O₂ → 2CO

- Reactants: 2 carbon (C) atoms, 2 oxygen (O) atoms.
- Products: 2 carbon (C) atoms, 2 oxygen (O) atoms.
- The equation is already balanced because the number of atoms of each element is the same on both sides.

Balanced Equation:
\[
\boxed{2C + O_2 \rightarrow 2CO}
\]

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2. 3H₂ + O₂ → 2H₂O

- Reactants: 6 hydrogen (H) atoms, 2 oxygen (O) atoms.
- Products: 4 hydrogen (H) atoms, 2 oxygen (O) atoms.
- To balance hydrogen, we need 6 H atoms on the product side. Since water (H₂O) has 2 H atoms per molecule, we multiply H₂O by 3:
\[
3H_2 + O_2 \rightarrow 3H_2O
\]
- Now, check oxygen: 2 O atoms on the reactant side, 3 O atoms on the product side. To balance oxygen, we multiply O₂ by 1.5, but since coefficients must be whole numbers, we multiply the entire equation by 2:
\[
6H_2 + 3O_2 \rightarrow 6H_2O
\]
- Simplify by dividing all coefficients by 2:
\[
3H_2 + \frac{3}{2}O_2 \rightarrow 3H_2O \quad \text{(not valid, so recheck)}
\]
- Correct approach: Multiply everything by 2 initially:
\[
6H_2 + 3O_2 \rightarrow 6H_2O
\]
Divide by 2:
\[
2H_2 + O_2 \rightarrow 2H_2O
\]

Balanced Equation:
\[
\boxed{2H_2 + O_2 \rightarrow 2H_2O}
\]

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3. CH₄ + Cl₂ → CH₃Cl + HCl

- Reactants: 1 carbon (C), 4 hydrogen (H), 2 chlorine (Cl).
- Products: 1 carbon (C), 3 hydrogen (H), 1 chlorine (Cl) in CH₃Cl, and 1 hydrogen (H), 1 chlorine (Cl) in HCl.
- Balance chlorine first: There are 2 Cl atoms on the reactant side, so we need 2 Cl atoms on the product side. Add a coefficient of 2 to HCl:
\[
CH_4 + Cl_2 \rightarrow CH_3Cl + 2HCl
\]
- Check hydrogen: 4 H atoms on the reactant side, 3 H atoms in CH₃Cl + 2 H atoms in 2HCl = 5 H atoms. This is not balanced. Re-evaluate:
\[
CH_4 + Cl_2 \rightarrow CH_3Cl + HCl
\]
Correct approach: The equation is already balanced as written.

Balanced Equation:
\[
\boxed{CH_4 + Cl_2 \rightarrow CH_3Cl + HCl}
\]

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4. Zn(OH)₂ + 2HCl → ZnCl₂ + 2H₂O

- Reactants: 1 zinc (Zn), 2 oxygen (O), 4 hydrogen (H), 2 chlorine (Cl).
- Products: 1 zinc (Zn), 2 chlorine (Cl), 4 hydrogen (H), 2 oxygen (O).
- The equation is already balanced because the number of atoms of each element is the same on both sides.

Balanced Equation:
\[
\boxed{Zn(OH)_2 + 2HCl \rightarrow ZnCl_2 + 2H_2O}
\]

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5. 2K + 2H₂O → 2KOH + H₂

- Reactants: 2 potassium (K), 4 hydrogen (H), 2 oxygen (O).
- Products: 2 potassium (K), 2 oxygen (O), 4 hydrogen (H).
- The equation is already balanced because the number of atoms of each element is the same on both sides.

Balanced Equation:
\[
\boxed{2K + 2H_2O \rightarrow 2KOH + H_2}
\]

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6. 2SO₂ + O₂ → 2SO₃

- Reactants: 2 sulfur (S), 4 oxygen (O).
- Products: 2 sulfur (S), 6 oxygen (O).
- To balance oxygen, add a coefficient of 2 to SO₃:
\[
2SO_2 + O_2 \rightarrow 2SO_3
\]
- Check sulfur: 2 S atoms on both sides. Check oxygen: 4 O atoms + 2 O atoms = 6 O atoms on the product side. The equation is balanced.

Balanced Equation:
\[
\boxed{2SO_2 + O_2 \rightarrow 2SO_3}
\]

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7. 2NO + O₂ → 2NO₂

- Reactants: 2 nitrogen (N), 4 oxygen (O).
- Products: 2 nitrogen (N), 4 oxygen (O).
- The equation is already balanced because the number of atoms of each element is the same on both sides.

Balanced Equation:
\[
\boxed{2NO + O_2 \rightarrow 2NO_2}
\]

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8. O₂ + C → CO₂

- Reactants: 2 oxygen (O), 1 carbon (C).
- Products: 1 carbon (C), 2 oxygen (O).
- The equation is already balanced because the number of atoms of each element is the same on both sides.

Balanced Equation:
\[
\boxed{O_2 + C \rightarrow CO_2}
\]

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9. C + H₂O → CO + H₂

- Reactants: 1 carbon (C), 2 hydrogen (H), 1 oxygen (O).
- Products: 1 carbon (C), 1 oxygen (O), 2 hydrogen (H).
- The equation is already balanced because the number of atoms of each element is the same on both sides.

Balanced Equation:
\[
\boxed{C + H_2O \rightarrow CO + H_2}
\]

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Final Answer:

\[
\boxed{
\begin{aligned}
1. & \ 2C + O_2 \rightarrow 2CO \\
2. & \ 2H_2 + O_2 \rightarrow 2H_2O \\
3. & \ CH_4 + Cl_2 \rightarrow CH_3Cl + HCl \\
4. & \ Zn(OH)_2 + 2HCl \rightarrow ZnCl_2 + 2H_2O \\
5. & \ 2K + 2H_2O \rightarrow 2KOH + H_2 \\
6. & \ 2SO_2 + O_2 \rightarrow 2SO_3 \\
7. & \ 2NO + O_2 \rightarrow 2NO_2 \\
8. & \ O_2 + C \rightarrow CO_2 \\
9. & \ C + H_2O \rightarrow CO + H_2 \\
\end{aligned}
}
\]