Which of the following chemical equations is an unbalanced one?

Options

A. `2NaHCO_(3)toNa_(2)CO_(3)+H_(2)O+CO_(2)`
B. `2C_(4)H_(10)+12O_(2)to8CO_(2)+10H_(2)O`
C. `2Al+6H_(2)Oto2Al(OH)_(3)+3H_(2)`
D. `4NH_(3)+5O_(2)to4NO+6H_(2)O`

Explanation

To determine which of the given chemical equations is unbalanced, we will analyze each option step by step.

### Step 1: Understand the concept of balanced and unbalanced equations
A balanced chemical equation has the same number of each type of atom on both the reactant side (left-hand side, LHS) and the product side (right-hand side, RHS). An unbalanced equation does not have the same number of atoms for each element on both sides.

### Step 2: Analyze each option

#### Option A:
**Equation:** 2 NaHCO3 → Na2CO3 + H2O + CO2

- **Count Sodium (Na):**
- LHS: 2 Na
- RHS: 2 Na (from Na2CO3)

- **Count Hydrogen (H):**
- LHS: 2 H (from 2 NaHCO3)
- RHS: 2 H (from H2O)

- **Count Carbon (C):**
- LHS: 2 C (from 2 NaHCO3)
- RHS: 2 C (1 from Na2CO3 and 1 from CO2)

- **Count Oxygen (O):**
- LHS: 6 O (from 2 NaHCO3)
- RHS: 3 O (from Na2CO3) + 1 O (from H2O) + 2 O (from CO2) = 6 O

**Conclusion:** This equation is balanced.

#### Option B:
**Equation:** 2 C4H10 + 12 O2 → 8 CO2 + 10 H2O

- **Count Carbon (C):**
- LHS: 8 C (from 2 C4H10)
- RHS: 8 C (from 8 CO2)

- **Count Hydrogen (H):**
- LHS: 20 H (from 2 C4H10)
- RHS: 20 H (from 10 H2O)

- **Count Oxygen (O):**
- LHS: 24 O (from 12 O2)
- RHS: 16 O (from 8 CO2) + 10 O (from 10 H2O) = 26 O

**Conclusion:** This equation is unbalanced because there are 24 O on the LHS and 26 O on the RHS.

#### Option C:
**Equation:** 4 Al + 3 O2 → 2 Al2O3

- **Count Aluminum (Al):**
- LHS: 4 Al
- RHS: 4 Al (from 2 Al2O3)

- **Count Oxygen (O):**
- LHS: 6 O (from 3 O2)
- RHS: 6 O (from 2 Al2O3)

**Conclusion:** This equation is balanced.

#### Option D:
**Equation:** 4 NH3 + 5 O2 → 4 NO + 6 H2O

- **Count Nitrogen (N):**
- LHS: 4 N (from 4 NH3)
- RHS: 4 N (from 4 NO)

- **Count Hydrogen (H):**
- LHS: 12 H (from 4 NH3)
- RHS: 12 H (from 6 H2O)

- **Count Oxygen (O):**
- LHS: 10 O (from 5 O2)
- RHS: 4 O (from 4 NO) + 6 O (from 6 H2O) = 10 O

**Conclusion:** This equation is balanced.

### Final Conclusion:
The unbalanced equation among the options is **Option B: 2 C4H10 + 12 O2 → 8 CO2 + 10 H2O**.

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