Question Discussion & Solution

Here the pattern is,

8 + 1² = 8 + 1 = 9

9 + 2² = 9 + 4 = 13

13 + 3² = 13 + 9 = 22 ¹ 27

22 + 4² = 22 + 16 = 38

Hence, 27 is the odd one out

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.

The Correct Answer is Option 4 i.e Propane.

• Methane:
  • Methane is a colorless odorless gas. 
  • It is also known as marsh gas or methyl hydride. 
  • The molecular formula is CH₄.
• Pentane:
  • Pentane is found in alcoholic beverages. 
  • Pentane is present in hop oil. 
  • Pentane is any or one of the organic compounds with the formula C₅H₁₂. 
  • Its properties are very similar to those of butane and hexane.
• Propane:
  • Propane, sometimes known as liquefied petroleum gas, or LPG.
  • Propane is a three-carbon alkane gas (C₃H₈).
  • Propane is produced as a by-product of natural gas processing and crude oil refining. 
• Butane:
  • Butane is a colorless gas with a faint petroleum-like odor.
  • It is shipped as a liquefied gas under its vapor pressure. 
  • Butane is a straight-chain alkane composed of 4 carbon atoms. 
  • C₄H₁₀ is the molecular formula of butane.

Concepts:

Physical Properties of Metals and Non-metals

Explanation:

• Iodine is lustrous. This is an exception to the physical properties of non - metals. Iodine is non-metal and non - metals have dull appearance. 
• Sodium is metal. Metals are usually hard so this is also an exception. 
• Graphite conducts electricity. This is an exception as graphite is a form of carbon and it is non - metal. 
• Copper being metal is not an exception as it is metals and metals are good conductors of heat. 

So the correct option is 'Copper is a good conductor of heat.'

The correct answer is All of the above.

Key Points

• Living organisms share characteristics such as the ability to move and reproduce.
• There are different types of living organisms including plants, animals, fungi, bacteria, and protoctists.
• Characteristics of living organisms:
  • Movement - they can move and change their position.
  • Reproduction – they can make more of the same kind of organism as themselves.
  • Sensitivity – they can detect or sense stimuli and respond to them.
  • Growth - they can permanently increase their size or dry mass by increasing the number or size of their cells.
  • Respiration – they can create chemical reactions that break down nutrient molecules in living cells to release energy.
  • Excretion – they can excrete toxic materials, waste products of metabolism, and excess substances.
  • Nutrition - they can take in and absorb nutrients such as organic substances and mineral ions. These nutrients contain the raw materials or energy needed for growth and tissue repair.

  Additional Information

• Cells are the building blocks of every living organism.
• Two-thirds of a cell is composed of water and is made up of biological molecules such as proteins and lipids.
• They provide a definite structure to the body, help to break down food, and release energy which is used up by our body to perform multiple tasks throughout the day.