General Science Questions (MCQs) for Competitive Examinations

Notes:
Sarpagandha plant is used to treat blood pressure. It’s one of the major source of resperine. The powder derived from Sarpagandha roots is an excellent natural remedy for treating hypertension. Sarpagandha lowers blood pressure and improves blood circulation by dilating the blood vessels and controlling nerve function in the muscles that lead to the heart.

Notes:
Greek thinker Aristotle was the first to attempt to classify all the kinds of animals in his History of Animals. He classified animals according to habitat; whether they lived on land, in water or in the air. He grouped the types of creatures according to their similarities : animals with blood and animals without blood, animals that live on water and animals that live on land.

Notes:
A heavy, silvery d-block element, Mercury is the only metal that is liquid at STP The only other elements that are liquid under these conditions is bromine.

Notes:
Aerated water is, correctly speaking, water to which air is added. So aerated water is any water artificially impregnated with a large amount of gas (carbon dioxide). The term is, however, frequently applied to carbonated water.

• H2O + CO2 —> H2OC3

Notes:
Stainless steel is an alloy of Iron with a minimum of 10.5% Chromium. Chromium produces a thin layer of oxide on the surface of the steel known as the ‘passive layer’ that prevents any further corrosion of the surface. Besides, Nickel and Molybdenum are added to impart other useful properties such as enhanced formability and increased corrosion resistance.

Notes:
The molar mass is the mass of a given chemical element or chemical compound (g) divided by the amount of substance (mol). The molar mass of the given noble gases are as follows:

• Argon (Ar): 39.9480 g/mol;
• Neon (Ne): 50.1858 g/mol;
• Krypton (Kr): 83.7980 g/mol;
• Xenon (Xe): 131.2930 g/mol.

Notes:
Carbon particles in air are colloidal in nature and carry negative charge. The removal of carbon particles from air involves the principle of electrophoresis. Carbon particles get precipitated by losing their charge and, thus, the air which finally comes out is free from them.

Notes:
Chernobyl disaster was a catastrophic nuclear accident that occurred on 26 April 1986 at the Chernobyl Nuclear Power Plant in the city of Pripyat, then located in the Ukrainian USSR. An explosion and fire released large quantities of radioactive particles into the atmosphere, which spread over much of the western USSR and Europe containing monazite.

Notes:
The Sun is a huge, glowing sphere of hot gas. Most of this gas is hydrogen (about 70%) and helium (about 28%). Carbon, nitrogen and oxygen make up 1.5% and the other 0.5% is made up of small amounts of many other elements such as neon, iron, silicon, magnesium and sulphur.

Notes:
Benzene can not undergo Elimination reaction.