Gaseous fuels due to their advantages over ther tupes of fuels are becoming highly popular . The advantages fo the fgaseous fuels are as follows :
a. High calorigic value .
b. Do not produce smoke and do not leave ash after combstion .
c. They can flow through pipes and can be ignige at a moment's notic eat any place . No sp-ecial devices are required for their combustion .
i. Coal gas is a good gaseous fuel as it conitains `95^5` combustible gaseous such as `H_2, CH_4, CO` etc , It is obtained buy destructive distillation of coal at ` 100^@ C` .
ii. Water gas is a mixture of ` CO` and `H_2` and is prepared by passing steam over incandescnt coke . The reaction is owever endothermic .
iii. Producer gas , which possesses low calorific value, so prepared by passing aair over red hot coke . It contains mainly nitrogen and ` CO`
iv. Semi-water gas is a mixture of water fas and producer fas .
v. oil gas , which is used in laboratries , is obtained by cracking of kerosene . It is a mixture of hydrocarbon (saturated and unsatureated ) mainly lower hudrocarons .
iv. `LPG`, which contains ` C_3` and ` C_4` hydrocarbon of the alkane and alkene serties , suppied in cylinders for domestic uses is very populsr these days .
Which one of following fuels has highest percentage of ` CO`?

Options

A. Coal gas
B. Water gas
C. Producer fas
D. Natural gas

Answer

To determine which gaseous fuel has the highest percentage of carbon monoxide (CO), we can analyze the composition of each fuel mentioned in the question.

### Step-by-Step Solution:

1. **Identify the Fuels and Their Compositions**:
- **Coal Gas**: Contains combustible gases such as hydrogen (H₂), methane (CH₄), and carbon monoxide (CO).
- **Water Gas**: A mixture of carbon monoxide (CO) and hydrogen (H₂).
- **Producer Gas**: Mainly consists of carbon monoxide (CO) and nitrogen (N₂).
- **Natural Gas**: Primarily composed of methane (CH₄) and ethane (C₂H₆), with negligible CO.

2. **Analyze Each Fuel for CO Content**:
- **Natural Gas**: Contains very little to no CO, so it can be eliminated.
- **Coal Gas**: While it contains CO, it also has significant amounts of H₂ and CH₄, which may reduce the percentage of CO.
- **Water Gas**: This is specifically a mixture of CO and H₂, typically having a high percentage of CO.
- **Producer Gas**: Contains CO but also has a significant amount of nitrogen, which may lower the percentage of CO compared to water gas.

3. **Comparison of CO Percentages**:
- **Water Gas**: Since it is primarily a mixture of CO and H₂, it is expected to have a higher percentage of CO compared to the other gases.
- **Producer Gas**: Although it contains CO, the presence of nitrogen dilutes the percentage of CO.
- **Coal Gas**: Contains CO but is mixed with other gases, which likely lowers its CO percentage.

4. **Conclusion**:
- Based on the analysis, **Water Gas** has the highest percentage of carbon monoxide among the listed gaseous fuels.

### Final Answer:
The fuel with the highest percentage of CO is **Water Gas**.

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