Question Discussion & Solution

The correct answer is Methane.

Key Points

• Methane (CH4)
  • It is the simplest hydrocarbon consisting of one carbon atom and four hydrogen atoms and the simplest hydrocarbon, is the most abundant hydrocarbon pollutant.
  • It is a powerful greenhouse gas.
  • Major natural sources of methane include emissions from wetlands, and oceans and from the digestive processes of termites.
  • Methane is more than 25 times as potent as carbon dioxide at trapping heat in the atmosphere.

Additional Information

• Butane is a gaseous component (at room temperature and atmospheric pressure) of the Alkane group having the chemical formula is C4H10.
• It is a colourless, highly flammable, and easily liquefied gas.
• In the abundance of oxygen, it forms Carbon dioxide, but if limited oxygen is available, then it forms Carbon Monoxide.

2C4H10 + 13O2 → 8CO2 + 10H2O                   (oxygen in plenty)

2C4H10 + 9O2 → 8CO + 10H2O                      (oxygen is limited)

• Uses –
  • Gasoline blending
  • Fuel gas
  • Fragrance extraction solvent
  • Feedstock for the manufacture of ethylene and butadiene
  • Ingredient for synthetic rubber
  • Isobutane to enhance the Octane number of gasoline in refineries.
• A propane molecule has three carbon atoms and eight hydrogen bonds and has the formula C3H8. 
• Propane is a colourless, easily liquefied, gaseous hydrocarbon (compound of carbon and hydrogen) and the third member of the paraffin series following methane and ethane.
• Propane is produced as a by-product of two other processes, natural gas processing and petroleum refining.
• It is separated in large quantities from natural gas, light crude oil, and oil-refinery gases and is commercially available as liquefied propane or as a major constituent of liquefied petroleum gas (LPG).
• Uses: 
  • It is used in LPG, also used as biofuel in buses and taxis and it is also the main gas in blowtorches and for hot air balloons.
  • Propane gas has become a popular choice for barbecues and portable stoves because its low boiling point makes it vaporize as soon as it is released from its pressurized container.
• The chemical formula of Ethane is C2H6.
• It is a colourless, odourless gas at normal temperature and pressure.
• It is extracted from natural gas on an industrial scale and is a petrochemical by-product of petroleum refining.
• Michael Faraday first synthesized it in 1834, using the electrolysis of a solution of potassium acetate.

President is the head of the Union Executive of a country.

Similarly,

The correct answer is Nitrification.

Key Points

• The process of conversion of ammonia into nitrate nitrogen is called nitrification.
• It is done in two steps- Nitrite formation, Nitrate formation.
• Nitrite formation- Ammonia are oxidized to nitrites by Nitrococcus, Nitrosomonas.

Additional Information

• The nitrogen cycle has four steps-
  • Nitrogen Fixation- Conversion of molecular nitrogen into the inorganic nitrogenous compound.
  • Ammonification- Conversion of the dead organic nitrogenous compound into ammonia.
  • Nitrification- Oxidation of ammonia into nitrates.
  • Denitrification- Nitrites or nitrates converts back into molecular nitrogen.

The correct answer is Tecomella Stenosis.

• Tecomella Stenosis is the scientific name of the state flower-Rohira of Rajasthan.

Key Points

• Rohira is the state flower of Rajasthan.
• Its scientific name is Tecomella Stenosis.
• The flower is mainly found in desert and barren areas of the Thar Desert, Rajasthan.

Additional Information

• Lilium is the scientific name of lily flower.
• Helianthus is the scientific name of sunflower.
• Psidium Guajava is the scientific name of Guava.

The correct answer is the Helium nucleus.

• Helium nucleus was the source of alpha particles in the Rutherford scattering experiment.
• Ernest Rutherford, a British scientist conducted an experiment and proposed the atomic structure of elements.

Key Points

• Rutherford conducted an experiment by bombarding a thin sheet of gold with α-particles.
• He then analysed the trajectory of these particles after their interaction with the gold foil.
• Since very few α-particles were deflected back, and only a few α-particles had nearly 180^o angle of deflection.
• Hence he concluded that the volume occupied by the positively charged particles in an atom is very small as compared to the total volume of an atom.