Defence GK Questions 2026

Manuel Aaron of Chennai earned the International Master title in 1961, the first Indian to hold any international chess title, and he dominated the national championship for close to two decades at a time when India had no professional circuit.

The award, instituted in 1991 and now named the Major Dhyan Chand Khel Ratna, went in its very first year to the chess Grandmaster Viswanathan Anand, who had turned Grandmaster three years earlier and was then rising rapidly in world chess.

Gukesh, from Chennai, won the Candidates Tournament in 2024 and then beat the defending champion Ding Liren of China in the title match held at Singapore later the same year, taking the crown at the age of eighteen and becoming the youngest undisputed world champion in the history of the…

The knight moves in the shape of the letter L, two squares along a rank or file and then one square at right angles, and it is the only piece that may pass over any piece standing in its way, its own or the opponent's. This is why a knight…

The date marks the founding of FIDE, the international chess federation, in Paris on 20 July 1924, and the day is observed by chess federations across the world with tournaments and school events.

FIDE, the Federation Internationale des Echecs, was founded in Paris in 1924, and its motto is Gens una sumus, a Latin phrase meaning we are one people.

A chessboard is a square divided into eight rows, called ranks, and eight columns, called files, so the number of squares is 8 multiplied by 8, that is 64.

Humpy, from Vijayawada in Andhra Pradesh, earned the open Grandmaster title in 2002 while in her teens, and at that time she was the youngest woman in the world to have done so.

Anand, born in Mayiladuthurai and brought up in Chennai, earned the Grandmaster title in 1988 while still a teenager and became the first Indian to hold the highest lifetime title awarded by FIDE.

Chaturanga was played in India in the Gupta age and its name means four limbs, standing for the four divisions of an ancient army: infantry, cavalry, elephants and chariots.

Bleaching powder, calcium oxychloride, is made in industry by passing chlorine gas over dry slaked lime, that is calcium hydroxide.

Tooth enamel is made of calcium phosphate, the hardest substance in the body, and it begins to corrode when the pH in the mouth drops below about 5.5.

A salt takes its character from the strength of the acid and the base that formed it. Ammonium chloride comes from hydrochloric acid, a strong acid, and ammonium hydroxide, a weak base, so the strong partner dominates and the solution has a pH below seven.

The stomach wall secretes hydrochloric acid, which makes the gastric juice strongly acidic, helps the enzyme pepsin digest proteins and kills many germs swallowed with food.

Plaster of Paris is calcium sulphate hemihydrate, made by heating gypsum, which is calcium sulphate dihydrate, to about 373 kelvin so that it loses three fourths of its water of crystallisation.

The sting of an ant and the hairs of the nettle plant inject formic acid, also called methanoic acid, which is why the skin burns; rubbing on a mild base such as baking soda or the leaf of the dock plant relieves it by neutralising the acid.

Baking soda is sodium hydrogen carbonate, a mild, non corrosive base used as an antacid, as an ingredient of baking powder along with a mild edible acid such as tartaric acid, and in soda acid fire extinguishers, where it releases carbon dioxide.

Borax, sodium tetraborate, is the salt of a strong base, sodium hydroxide, and a weak acid, boric acid, so its solution in water is basic.

The pH is the negative logarithm of the hydrogen ion concentration, so each rise of one unit means the concentration has fallen to one tenth.

Citrus fruits such as orange, lemon, lime and grapefruit owe their sharp sour taste to citric acid, which is the acid textbooks name for this family and the one examiners expect here.