Question Discussion & Solution

The correct answer is 7.

Key Points

• The pH value of salts of strong acid and strong base is 7.
  • The salts are from a strong acid and strong base do not hydrolyze and the resulting salt pH will remain 7.
  • The anion in the salt form's strong base does not attract the H+ from the water.

Additional Information

• Salt of a strong acid and a weak base is acidic with a pH value less than 7 because acid is strong which retains the pH value less than 7.
• Salt of a weak acid and strong base is basic with a pH value of more than 7 because the base is strong hence pH of the whole solution will be more than 7.
• Salt of a strong acid and strong base is neutral because both are strong and cancels strong effects of each other, the pH will be 7.

Letters are replaced by their place values as in the general alphabetical series.

Similarly,

Hence, answer is '14935'.

The correct answer is Butane.

Key Points 

• Liquefied Petroleum Gas (LPG) is a blend of light hydrocarbon compounds.
  • It mainly consists of butane or propane or a mixture of both.
  • At room temperature, both gases are colourless and odourless.
  • It is a mixture of 48% propane, 50% butane, and 2% pentane.

Additional Information

• Water Gas:
  • Water-gas is a mixture of CO and H₂.
  • However, by-products such as char, tar, soot, ash, and condensates are also produced. 
• Natural gas is a naturally occurring hydrocarbon gas mixture consisting primarily of methane, but commonly including varying amounts of other higher alkanes, and sometimes a small percentage of carbon dioxide, nitrogen, hydrogen sulfide, or helium.
• Compressed natural gas is a fuel that can be used in place of petrol (gasoline), diesel fuel, and liquefied petroleum gas (LPG).
  • CNG combustion produces fewer undesirable gases than the aforementioned fuels.
  • In comparison to other fuels, natural gas poses less of a threat in the event of a spill, because it is lighter than air and disperses quickly when released.

The correct answer is Vitamin A.

• Vitamin A causes Night Blindness.

Key Points

• Night blindness is a type of vision impairment also known as nyctalopia. People with night blindness experience poor vision at night.
• Vitamin was first invented by FG Hopkins.  However, the term vitamin was coined by C Funk. 
• Good sources of vitamin A include cheese, eggs oily fish.

Additional Information

• Vitamin B₁₂ deficiency may lead to a reduction in healthy red blood cells (anaemia). 
• Vitamin C is found in citrus fruits and vegetables.
  • Scurvy results from a deficiency of vitamin C in the diet.
• The signs and symptoms of vitamin D deficiency include Fatigue, Bone pain, muscle weakness, muscle aches, or muscle cramps.
  • Rickets is caused due to deficiency of vitamin D
• Vitamin E deficiency can cause nerve and muscle damage loss of body movement control, muscle weakness, and vision problems.

The correct answer is Accumulator.

Key Points

• An accumulator is a type of register present in a CPU (Central Processing Unit).
• It works as a temporary storage location that keeps an intermediate value in logical and mathematical calculations.
• Intermediate results of execution are progressively stored in the accumulator, replacing the previous value.

Additional Information

• An IR (Instruction Register) saves machine instruction that is currently under execution. It is a register that sits at the top of the memory hierarchy. A variety of registers fulfills different operations in a central processing unit (CPU) – the function of the IR is to keep that currently stacked instruction for use.
• A PC (program counter) is a CPU register that has the address stored for the next instruction to be processed from memory. It is a digital counter required for quicker execution of tasks as well as to keep track of the current execution point. 
• The MAR (Memory Address Register) is the register in the control unit that holds the address of a register to receive or store from or to the storage. The Memory Address Register is half of an interaction between a microprogram and storage.