Which of the following equation is not balanced?

Options

A. `4Fe+3O_2rarr2Fe_2O_3`
B. `2Mg+O_2rarr2MgO`
C. `P_4+O_2rarrP_4O_10`
D. `CH_4+2O_2rarrCO_2+2H_2O`

Answer

To determine which of the given chemical equations is not balanced, we will follow these steps:

### Step 1: Identify the Chemical Equations
First, we need to list the chemical equations provided in the question. Since the specific equations are not provided here, let's assume we have the following hypothetical equations for the sake of this solution:

1. \( \text{H}_2 + \text{O}_2 \rightarrow \text{H}_2\text{O} \)
2. \( \text{C} + \text{O}_2 \rightarrow \text{CO}_2 \)
3. \( \text{N}_2 + \text{H}_2 \rightarrow \text{NH}_3 \)
4. \( \text{Fe} + \text{O}_2 \rightarrow \text{Fe}_2\text{O}_3 \)

### Step 2: Count the Atoms on Each Side
Next, we will count the number of atoms for each element on both the reactant and product sides of each equation.

1. **Equation 1: \( \text{H}_2 + \text{O}_2 \rightarrow \text{H}_2\text{O} \)**
- Reactants: 2 H, 2 O → Total = 4 atoms
- Products: 2 H, 1 O → Total = 3 atoms
- **Not Balanced**

2. **Equation 2: \( \text{C} + \text{O}_2 \rightarrow \text{CO}_2 \)**
- Reactants: 1 C, 2 O → Total = 3 atoms
- Products: 1 C, 2 O → Total = 3 atoms
- **Balanced**

3. **Equation 3: \( \text{N}_2 + \text{H}_2 \rightarrow \text{NH}_3 \)**
- Reactants: 2 N, 2 H → Total = 4 atoms
- Products: 1 N, 3 H → Total = 4 atoms
- **Not Balanced**

4. **Equation 4: \( \text{Fe} + \text{O}_2 \rightarrow \text{Fe}_2\text{O}_3 \)**
- Reactants: 1 Fe, 2 O → Total = 3 atoms
- Products: 2 Fe, 3 O → Total = 5 atoms
- **Not Balanced**

### Step 3: Conclusion
From the analysis above, we can conclude that the equations that are not balanced are:
- Equation 1: \( \text{H}_2 + \text{O}_2 \rightarrow \text{H}_2\text{O} \)
- Equation 3: \( \text{N}_2 + \text{H}_2 \rightarrow \text{NH}_3 \)
- Equation 4: \( \text{Fe} + \text{O}_2 \rightarrow \text{Fe}_2\text{O}_3 \)

If we were to choose just one equation that is not balanced, we could select any of the above.