Problem 53 - A Complete Resource Book in Chemistry for JEE Main

Question

The poisonous gas present in the exhaust fumes of car is (a) \(\mathrm{CO}_{2}\) (b) \(\mathrm{CO}\) (c) \(\mathrm{CH}_{4}^{-}\) (d) \(\mathrm{C}_{2} \mathrm{H}_{2}\)

Step-by-Step Solution

Answer

The poisonous gas in car exhaust is carbon monoxide (\(\mathrm{CO}\)).

Step 1: Understand the Chemicals

Let's look at what each chemical formula represents. - \(\mathrm{CO}_{2}\) is carbon dioxide, a common gas in the atmosphere.-\(\mathrm{CO}\) is carbon monoxide, a colorless, odorless, and toxic gas.-\(\mathrm{CH}_{4}^{-}\) is an incorrect notation for methane, which is a harmless flammable gas.-\(\mathrm{C}_{2}\mathrm{H}_{2}\) is acetylene, a gas used in welding.

Step 2: Identify Poisonous Gas in Car Exhaust

Car exhaust fumes typically contain a mixture of gases. Among them, carbon monoxide (\(\mathrm{CO}\)) is known for being poisonous because it can bind to hemoglobin in the blood, reducing oxygen transport.

Step 3: Determine Which Gas Causes Harm

The key factor in identifying the harmful gas is recognizing its ability to be a health hazard. While carbon dioxide is non-poisonous at typical levels and acetylene is not usually found in exhaust, carbon monoxide is indeed poisonous.

Step 4: Select the Correct Answer

Based on the above information, the poisonous gas present in the exhaust fumes of a car is carbon monoxide (\(\mathrm{CO}\)). Therefore, the correct answer is (b) \(\mathrm{CO}\).

Key Concepts

carbon monoxide

Carbon monoxide (CO) is a colorless, odorless gas that is highly poisonous. It is produced when carbon-containing fuels such as gasoline, wood, coal, or natural gas are burned incompletely. Because it is undetectable by human senses, it's often referred to as a 'silent killer'. This gas becomes particularly dangerous when it accumulates in enclosed spaces, replacing oxygen in the air.

CO poisoning occurs because it binds with hemoglobin in red blood cells, forming carboxyhemoglobin. This reduces the blood's ability to carry oxygen to cells and tissues. Exposure symptoms can include headache, dizziness, weakness, confusion, and if severe, can lead to unconsciousness or even death. Therefore, it's crucial to have CO detectors in homes, especially near appliances that burn fuel.

car exhaust fumes

Car exhaust fumes are the gases emitted from the exhaust system of a vehicle. These fumes are a mix of various gases, many of which can be harmful to human health and the environment. Primarily, they consist of nitrogen, oxygen, water vapor, carbon dioxide, and sadly, carbon monoxide along with traces of hydrocarbons and nitrogen oxides.

The presence of carbon monoxide in car exhaust is a major safety concern. Vehicles contribute significantly to air pollution, particularly when they are poorly maintained or driven inefficiently. Efforts to reduce emissions include improving fuel quality, advancing vehicle technology, and implementing stricter regulations for emissions control for cleaner air.

• Regular vehicle maintenance is essential to reduce harmful emissions.
• Choosing fuel-efficient and less-polluting cars can help the environment.

chemical formulas

Chemical formulas are a shorthand method for representing chemical substances using symbols for the elements involved and numerical subscripts indicating the number of atoms of each element. They provide essential information about a chemical substance's composition.

For example, the formula \(\text{CO}_{2}\) represents carbon dioxide with one carbon atom and two oxygen atoms, whereas \(\text{CO}\) stands for carbon monoxide, comprising one carbon and one oxygen atom.

Understanding these formulas helps identify the different gases present in various environments, such as in car exhaust fumes, aiding in the detection of potentially harmful substances.

• Remember, subscripts show the number of atoms for each element in the molecule.
• Recognizing chemical formulas can lead to better awareness of environmental and health impacts.