Greenhouse Gases and Atmosphere

Some amount of phosphorus is returned to the earth, in the form of bird's excreta - Guano deposits (excreta of marine birds) and dead fish (around 60,000 tonnes which is less than 0.5% of phosphorus discharged from rivers)

The high concentration of CO₂ in atmosphere has been the main component of the greenhouse effect, which has caused global warming, i.e. the rise of atmospheric temperature in recent years.

This is the correct answer. Animals and humans release carbon dioxide and breathe in oxygen during the process of respiration.

Carbon dioxide is a primary greenhouse gas that traps heat in the atmosphere. Sulphur dioxide and nitric oxide are primarily associated with acid rain and smog, while ethane is a hydrocarbon fuel.

This is the correct option. The natural gas contains ethane and propane in small quantities, the major quantity being methane.

This is the correct option. Carbon dioxide is a greenhouse gas.

It is the percentage of carbon dioxide gas. The raising level of carbon dioxide and methane, in the atmosphere is the major cause for global warming. It is because of the increasing greenhouse gases, that raises the concern of melting of glaciers and elevation, in the global temperature.

This is the correct option. Carbon dioxide is useful for plants in making their food through the process of photosynthesis.

Biogas is primarily composed of methane (CH4), which typically makes up 50 to 75 percent of the gas mixture. Other components include carbon dioxide and trace amounts of hydrogen sulfide.

Ans - 4

LPG (Liquefied Petroleum Gas) is primarily composed of propane and butane. While both are constituents, propane is often cited as a major component in many standard mixtures.

Ans - 1

The concentration of carbon dioxide in the Earth's atmosphere is approximately 0.03 to 0.04 percent by volume. Among the choices provided, 0.03% is the standard accepted value.

Carbon dioxide is the primary greenhouse gas emitted through human activities, such as burning fossil fuels, and is the main driver of the greenhouse effect.