Heat of combustion of carbon monoxide is -283.5 kJ/mole. The heat released when 55 g of carbon dioxide formed from carbon monoxide is

Options

A. 283.5 kJ
B. 324.2 kJ
C. 354.4 kJ
D. 385.5 kJ

Answer

To find the heat released when 55 g of carbon dioxide (CO2) is formed from carbon monoxide (CO), we can follow these steps:

### Step 1: Understand the heat of combustion
The heat of combustion of carbon monoxide (CO) is given as -283.5 kJ/mole. This means that when 1 mole of CO is combusted, 283.5 kJ of heat is released.

### Step 2: Determine the molar mass of CO2
The molar mass of carbon dioxide (CO2) can be calculated as follows:
- Carbon (C) has a molar mass of approximately 12 g/mol.
- Oxygen (O) has a molar mass of approximately 16 g/mol.
- Therefore, the molar mass of CO2 = 12 + (2 × 16) = 12 + 32 = 44 g/mol.

### Step 3: Calculate the number of moles of CO2 in 55 g
To find the number of moles of CO2 in 55 g, we use the formula:
\[ \text{Number of moles} = \frac{\text{mass (g)}}{\text{molar mass (g/mol)}} \]
Substituting the values:
\[ \text{Number of moles of CO2} = \frac{55 \, \text{g}}{44 \, \text{g/mol}} = 1.25 \, \text{moles} \]

### Step 4: Calculate the heat released for 1.25 moles of CO2
Since the heat of combustion for 1 mole of CO produces 1 mole of CO2 and releases -283.5 kJ, we can calculate the heat released for 1.25 moles:
\[ \text{Heat released} = \text{Number of moles} \times \text{Heat of combustion} \]
Substituting the values:
\[ \text{Heat released} = 1.25 \, \text{moles} \times (-283.5 \, \text{kJ/mole}) = -354.375 \, \text{kJ} \]

### Step 5: Round off the answer
The heat released when 55 g of carbon dioxide is formed from carbon monoxide is approximately:
\[ \text{Heat released} \approx -354.4 \, \text{kJ} \]

### Final Answer
The heat released when 55 g of carbon dioxide is formed from carbon monoxide is -354.4 kJ.

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