Combustion of Fossil Fuels

The process in which carbon react with oxygen to produce carbon dioxide and water is called

• oxidation

• fermentation

• photosynthesis

• combustion

Answer explanation

The process where carbon reacts with oxygen to produce carbon dioxide and water is known as combustion. This exothermic reaction releases energy, distinguishing it from other processes like fermentation and photosynthesis.

One of the element found abundantly in the atmosphere in form of carbon dioxide is

• Nitrogen

• Hydrogen

• Oxygen

• carbon

Answer explanation

Carbon is a key element in the atmosphere, primarily found in the form of carbon dioxide (CO2). The other options, nitrogen, hydrogen, and oxygen, do not exist as carbon dioxide.

The chemical reaction that involves the combination of oxygen with a substance to produce heat and light is known as

• sublimation

• reduction

• oxidation

• evaporation

Answer explanation

The reaction described is oxidation, which involves oxygen combining with a substance, releasing heat and light. This distinguishes it from sublimation, reduction, and evaporation, which do not involve this specific process.

Which gas is primarily responsible for the greenhouse effect in the atmosphere?

• Nitrous Oxide

• Carbon Dioxide

• Ozone

• Methane

Answer explanation

Carbon Dioxide is the primary greenhouse gas, significantly contributing to the greenhouse effect by trapping heat in the atmosphere. While other gases like methane and nitrous oxide also play a role, CO2 is the most abundant and impactful.

The process by which green plants use sunlight to synthesize foods with the help of carbon dioxide and water is called

• respiration

• transpiration

• photosynthesis

• decomposition

Answer explanation

The correct answer is photosynthesis, which is the process by which green plants use sunlight, carbon dioxide, and water to create food. Respiration and transpiration are different processes, while decomposition involves breaking down organic matter.

Another name for combustion is

• burning

• smoldering

• explosion

• oxidation

Answer explanation

Combustion is a chemical reaction that produces heat and light, commonly referred to as burning. While smoldering and oxidation are related processes, burning is the most direct synonym for combustion.

One of these is not an example of Non-renewable energy source

• Oil

• Solar energy

• Natural gas

• Coal

Answer explanation

Solar energy is a renewable energy source, while oil, natural gas, and coal are non-renewable. Therefore, solar energy is the correct answer as it does not belong to the category of non-renewable energy sources.

The following are examples of renewable energy source except

• hydropower

• wind energy

• solar energy

• fossil fuels

Answer explanation

Fossil fuels, such as coal and oil, are non-renewable energy sources that take millions of years to form. In contrast, hydropower, wind energy, and solar energy are renewable, as they can be replenished naturally in a short time.

It takes ------- years to produce fossil fuel

• hundreds of years

• decades

• millions of years

• thousands of years

Answer explanation

Fossil fuels are formed from the remains of ancient organisms over geological time. This process takes millions of years, making 'millions of years' the correct choice compared to the other options.

The hydrocarbon with the molecular formula CH4 is

Answer explanation

The hydrocarbon with the molecular formula CH4 is methane. Methane is the simplest alkane and consists of one carbon atom bonded to four hydrogen atoms.