Practice MCQ Questions and answers on Chemistry-GK

Flourine is the most reactive gaseous element.

A native metal is any metal that is found in its metallic form, either pure or as an alloy, in nature. Metals that can be found as native deposits singly and/or in alloys include aluminium, antimony, arsenic, bismuth, cadmium, chromium, cobalt, indium, iron, nickel, selenium, tantalum, tellurium, tin, titanium, and zinc, as well as two groups of metals: the gold group, and the platinum group. The gold group consists of gold, copper, lead, aluminium, mercury, and silver.

Gold, which is not only the most valuable of metals, but also is without its peer in freedom from alloy, is known as the king of metals. Luxurious, classy and beautiful, gold is the most classic and coveted jewelry metal of all. It is also the oldest precious metal known to man.

Titanium alloy, which has high corrosion resistance, high specific strength, and good heat resistance, is used for different spacecraft parts including outer fuel tank sheathing and wings. It is extremely strong at high temperatures.

White phosphorus is highly reactive, and spontaneously ignites at about 30°C in moist air. It is usually stored under water, to prevent exposure to the air. It is also extremely toxic, even in very small quantities.

Vulcanization gives rubber its characteristic elastic quality. This process is carried out by mixing the latex with sulphur (other vulcanizing agents such as selenium and tellurium are occasionally used but sulphur is the most common) and heating it in one of two ways.

Quicksilver is an alternative name for the element mercury. A heavy, silvery d-block element, mercury is the only metal that is liquid at standard conditions for temperature and pressure; the only other element that is liquid under these conditions is bromine, though metals such as caesium, gallium, and rubidium melt just above room temperature.

The number 6.023 ×10²³ is known as Avogadro’s Number which is the number of atoms in 12g of the isotope carbon-12. 6.023 ×10²³ carbon atoms weigh = 12 grams.

There are two million chloride ions.

The mass percentage of carbon in carbon dioxide is 27.3 %.