UPSC Civil Services GK Questions 2026

The word comes from the Greek for tree, and the pattern develops where the underlying rock is of uniform hardness and the slope is gentle, so the streams branch freely without being guided by lines of weakness; the tributaries of the Ganga in the northern plain are the standard Indian…

It is the reason one mole of every gas occupies the same 22.4 litres at standard temperature and pressure, and it allowed chemists to settle the formulae of gases such as hydrogen and oxygen as having two atoms each.

When two elements form more than one compound, the masses of one element that combine with a fixed mass of the other bear a simple whole number ratio, and here the oxygen masses of sixteen and thirty two grams for the same twelve grams of carbon are in the ratio…

The molecular mass of water is eighteen unified atomic mass units, two hydrogen atoms of 1 u each and one oxygen atom of 16 u, so one mole of water weighs eighteen grams.

This standard was adopted so that the atomic masses of all elements could be compared on one relative scale, and on it hydrogen comes out as about 1 u, oxygen as 16 u and chlorine as 35.5 u. Option A is wrong because the hydrogen atom was the standard in…

It follows from Avogadro's law: since equal volumes of all gases at the same temperature and pressure contain an equal number of molecules, one mole of hydrogen, of oxygen or of carbon dioxide all take up the same space at standard temperature and pressure, even though their masses are two…

It is the number of atoms in twelve grams of carbon twelve, and it holds for atoms, molecules, ions or electrons alike, so one mole of water has that many water molecules and one mole of sodium has that many sodium atoms.

Calcium chloride is an ionic compound, so the sum of the atomic masses in its formula is called the formula unit mass rather than the molecular mass.

The formula of ammonia is NH3, so its molecular mass is the atomic mass of one nitrogen atom added to the atomic masses of three hydrogen atoms, that is fourteen plus three times one, which equals seventeen unified atomic mass units; one mole of ammonia therefore weighs seventeen grams.

Water drawn from a river, from rain or made in a laboratory always has hydrogen and oxygen in the mass ratio of one to eight, and ammonia always has nitrogen and hydrogen in the ratio of fourteen to three.

The correct answer is B, Antoine Lavoisier, the French chemist who showed by careful weighing in closed vessels that the total mass of the products of a reaction is exactly equal to the total mass of the reactants, so that matter is neither created nor destroyed in a chemical change.

According to the Supreme Court of India, Justice Surya Kant was elevated as a judge of the Supreme Court on 24 May 2019 and was sworn in as the fifty-third Chief Justice of India on 24 November 2025, with retirement due on 9 February 2027.

Justice Y. V. Chandrachud was Chief Justice of India from 1978 to 1985 and his son, Justice D. Y. Chandrachud, became the fiftieth Chief Justice of India in November 2022, the only instance of a father and a son both holding the office.

Article 126 provides that when the office of Chief Justice of India is vacant, or when the Chief Justice is by reason of absence or otherwise unable to perform the duties of the office, the duties shall be performed by such one of the other judges of the Court as…

Article 124(2) provides that a judge of the Supreme Court holds office until he attains the age of sixty-five years, and the Chief Justice of India is a judge of that Court, so the same limit applies to him.

Article 60 lays down the form of oath for the President and provides that it is made in the presence of the Chief Justice of India, or in his absence the senior-most judge of the Supreme Court available.

Justice Kamal Narain Singh was Chief Justice of India for only seventeen days, from 25 November to 12 December 1991, the shortest tenure in the history of the office.

Justice Yeshwant Vishnu Chandrachud was Chief Justice of India from 22 February 1978 to 11 July 1985, a tenure of about seven years and four months, by far the longest any holder of the office has had.

Justice Mohammad Hidayatullah, who was Chief Justice of India from 1968 to 1970, officiated as President of India from 20 July to 24 August 1969, in the gap between the death of President Zakir Husain and the election of V. V. Giri.

Article 124 establishes the Supreme Court of India and lays down that every judge of the Court, including the Chief Justice of India, is appointed by the President by warrant under his hand and seal; Article 124(2) fixes the retirement age at sixty-five years and Article 124(4) prescribes the procedure…