Question Discussion & Solution

Concept:

System modelling is the process of developing abstract models of a system and each model presenting a different view or perspective of that system. 

Explanation:

Concept that has to be considered while modelling a new system are:

Abstraction: at highest level of abstraction, a solution is stated in broad terms while at the lowest level of abstraction a more detailed solution is provided.

Modularity: it is the single attribute of the software that allows a program to be individually manageable.

Information hiding in this algorithms and data contained within a module are inaccessible to to other modules.

Some other factors that are considered are: architecture, pattern, functional independence, refinement, refinement. 

The correct answer is During 1982-83.

• Maharana Pratap Khel Award was instituted during 1982-83.

Key Points

• Maharana Pratap Khel Award:
  • The award is given by the State Sports Council for outstanding achievements at the National and International levels.
  • It was instituted in the year 1982-1983.
  • The awards consist of:
    • A Citation
    • Bronze Statue of Maharana Pratap

    • Cash prize of INR 1,00,000.

• Vashisth Puraskar is given to the outstanding Sports Coach of the state.
• Ashok Chandan is the current Sports Minister.

Additional Information

• Rajiv Gandhi Khel Ratna Award:
  • The Rajiv Gandhi Khel Ratna Award is India’s highest honour given for achievement in sports.
  • The award was instituted in the year 1991-92.
  • Vishwanathan Anand is the first winner of the award.

Explanation:

Composting is one of the options for the treatment of solid waste. In the composting process, the organic matter breaks down under bacterial action resulting in the formation of humus like material called compost.

• Vermicomposting: It involves the use of earthworms for composting organic solid waste. It is a resourceful way to recycle your food waste into compost. It takes about 2-3 months.
• Vermicompost (worm manure) is the end-product of the breakdown of organic matter by earthworms. 
• This process of increasing the fertility of soil by earthworms is known as vermicomposting.

Hence, fertilizer produced by the earthworm is called Vermicompost.

Additional Information

Biofertilizers: 

• ​Is a substance that contains living micro-organisms that, when applied to seeds, plant surfaces, or soil, colonize the rhizosphere or the interior of the plant and promotes growth by increasing the supply or availability of primary nutrients to the host plant. 
• Biofertilizers add nutrients through the natural processes of Nitrogen fixation.
• Examples: Rhizobium, Azotobacter, Blue-green algae, Azospirilium.

Nitrogen fertilizer:

• Urea, also known as carbamide, is an organic compound with the chemical formula CO(NH₂)₂.
• This amide has two –NH₂ groups joined by a carbonyl functional group.
• Urea serves an important role in the metabolism of nitrogen-containing compounds by animals and is the main nitrogen-containing substance in the urine of mammals.
• The main function of Urea fertilizer is to provide the plants with nitrogen to promote green leafy growth and make the plants look lush.
• Urea has the highest nitrogen content of all solid nitrogenous fertilizers in common use.

Concept:

• Atoms are made up of subatomic particles - electrons protons and neutrons.
• In the center of an atom, a nucleus is present which contains protons and neutrons together known as nucleons.
• The mass of an atom is most concentrated at the center of the atom, i.e. the nucleus.

​Electrons:

• Discovered by Sir J.J Thomson in the year 1897.
• Previously named as cathode rays as they were supposed to be emitted from the cathode.
• They are deflected towards the positive side.
• They have high kinetic energy.
• They are deflected by an electric and magnetic field.
• It has a negative charge of

  \(charge=1.602\times10^{-19} coulombs \)
\(mass={1\over 1837}\times 9.107\times 10^{-28}g\)

Protons:

• Discovered by Goldstein.
• Depicted first as positive rays because it seemed to emerge from the anode.
• Mass of a proton is

 \(1.670 \times 10^{- 24}g\)

\(Charge=1.602\times 10^{-19} coulombs\)​

Explanation:

• Rutherford's discovery led to the discovery of nucleus.
• He found out that most of the mass of the nucleus is situated in its centre and contains the positively charged particles protons.
• The atom is otherwise empty and as electrons have negligible mass, the mass of an atom should be equal to the sum of mass of protons present in it.
• However, it was seen that in Helium, there are only two protons, so its mass should be twice the mass of each proton = \(2\times 1.008 a.m.u\).
• Experimental results revealed that it has a mass of 4.003a.m.u.
• Hence, it was concluded that the nucleus has particles containing no charge but mass almost equal to that of a proton.
• This was established by scientist James chadwick in 1932.

Additional Information

Rutherford's gold foil experiment: 

• He discovered the atomic nucleus and gave us an atomic model.
• He directed alpha particles towards a metal sheet.
• He saw that most of the alpha particles, which are positively charged particles, are not getting deflected.
• Most of the alpha particles emerged undeflected.

• Therefore, he concluded that most of the mass of the nucleus is situated in its centre and contains the positively charged particles protons.
• Electrons revolve around the nucleus in certain orbits.

The correct answer is Hydrocarbons.

Key Points

• The compounds which are formed by the covalent bond between carbon & hydrogen, are known as hydrocarbons.
• These are also known as 'parent compound'.
• Carbon is placed in the Second period.
• The atomic number of carbon is 6 while the weight is 12.
• Carbon needs 4 electrons to complete the octet state and it is full filled by covalent bonds.

Additional Information

•  Examples of Hydrocarbon.
• Natural Gas:
  • Natural gas contains 97% of Methane.
  • It is a colourless highly flammable gaseous hydrocarbon.
  • It is used as fuel for generating electricity and heat.
  • Natural gas is a compressed form that is used as fuel for vehicles which is known as CNG.
  • This is used for making fertilizers also, mainly ammonia.
• Methane:
  • Methane was discovered by the Italian scientist Alessandro Volta between 1776-1778 while he was studying the gases found in marshy land.
  • Melting Point- -182.5 degree
  • Boiling point- -161.5 degree
  • Methane gas is colourless and is less dense than water.
  • This gas is highly inflammable. While burning with oxygen it has a bluish flame.