General Science Previous Year Questions (PYQ) with Answers – Page 60

Only vitamin C and the eight vitamins of the B complex dissolve in water; the rest dissolve in fat.

The B complex is a group of eight water soluble vitamins that work mainly as helpers in the reactions that release energy from food.

Cinnabar is mercuric sulphide, HgS, and the formula itself gives the answer away because Hg is the symbol of mercury.

In a prokaryotic cell the genetic material lies free in the cytoplasm with no nuclear membrane around it, and this poorly defined nuclear region is called the nucleoid.

Copper sulphate holds five water molecules, sodium carbonate ten and gypsum two, so the order asked for is 5, 10 and 2.

A clinical thermometer is marked from 35 to 42 degrees Celsius, which on the Fahrenheit scale is 94 to 108 degrees.

In the colour code used for fire extinguishers, a black band or label marks a carbon dioxide extinguisher. The body of the cylinder is signal red and a coloured patch near the label tells you the filling at a glance, so the right cylinder can be picked in a hurry.

Fires are sorted into classes by what is burning, and Class A covers ordinary solid fuels — wood, paper, cloth, straw, rubber and many plastics.

Crown gall is caused by the bacterium Agrobacterium tumefaciens, which enters through a wound near the base, or crown, of the stem and makes the plant grow rough tumour-like swellings there.

Animal tissues are grouped into four kinds — epithelial, muscular, connective and nervous — and areolar is not one of them, because it is only a type of connective tissue.

A wet chemical extinguisher sprays a fine mist of a potassium salt solution — usually potassium acetate, potassium citrate or potassium carbonate — so potassium is the working element inside it.

High-speed steel is named 18-4-1 after the three metals added to it in that order: 18 per cent tungsten, 4 per cent chromium and 1 per cent vanadium, with iron making up the rest along with a little carbon.

Chadwick discovered the neutron in 1932 and won the Nobel Prize in Physics for it in 1935. He bombarded beryllium with alpha particles and found that the radiation given off was not affected by electric or magnetic fields, yet could knock protons out of paraffin.

only. In a permanent magnet moving coil instrument the coil is pivoted in the field of a permanent magnet, so the deflecting torque is proportional to the current itself and not to its square.

Distillation separates a liquid from a solution or from another liquid by boiling it and condensing the vapour, so it is used when the components differ in boiling point, as in getting pure water from salt water or separating acetone from water.

Absolute pressure is counted from the absolute zero of pressure, which is a perfect vacuum, so it can never be negative.

Potential difference between two points of a circuit is the difference in electric potential between them, and it equals the work done in moving a unit positive charge from one point to the other.

The name itself says so: in Greek arthros means jointed and podos means foot, so arthropods are the animals with jointed legs.

Newton passed a narrow beam of sunlight through a glass prism in a darkened room and obtained a band of seven colours on the wall, which he named the spectrum.

Geitonogamy is the transfer of pollen grains from the anther of one flower to the stigma of another flower on the same plant.