Element, Compound or Mixture? Trivia Quiz

Answer: mixture

The constituents of a mixture can easily be separated by physical processes, which in this case, was the application of heat. The salt had been dissolved in the water to form a true solution of common salt, where the particles of salt were invisible through the naked eye as well as through a microscope, resulting in the solution being absolutely clear.

Answer: element

Gold, like oxygen, hydrogen and over 100 other substances is classified as an element. Elements are further grouped into metals, non-metals and metalloids.

22-carat (or "karat") gold, or 22 parts of gold alloyed with 2 parts of silver or copper, is usually preferred to 24-carat (pure) gold in jewellery.

Answer: mixture

The powder was a mixture of sulphur, which is yellow in colour, and iron, which is magnetic and blackish in colour. When the magnet was passed over the mixture, the iron got attracted to it, leaving the sulphur in the dish. Hence in mixtures, the properties of the constituents aren't lost.

Answer: element

An element is a substance which contains only one kind of atom. Oxygen contains only atoms of oxygen, uranium contains only atoms of uranium, sodium contains only atoms of sodium. The structure of the atoms of an element defines its properties.

Answer: compound

A molecule of water is made up of two atoms of hydrogen and one atom of oxygen, which means that it is made up of more than one kind of atom, and hence isn't an element. Also, since it can only be broken down into hydrogen and oxygen (its constituent elements) by chemical processes (such as electrolysis), it is a compound.

Answer: mixture

Aqua regia was a mixture of concentrated nitric acid (HNO3) and hydrochloric acid (HCl) and was used to dissolve gold, which would leave silver.

Answer: element

As you probably guessed, the gas is *oxygen*, of which the molecular formula is 'O2'.

Answer: compound

Magnesium oxide is made up of atoms of two different kinds - magnesium and oxygen, and hence is not an element. The ratio of magnesium : oxygen in it is a constant 1:1, and hence it is a compound.

Answer: mixture

Air is a mixture of several gases, with each of them retaining their own properties. Here's a brief outline of the composition of the air we breathe: Nitrogen - 78.1%; Oxygen - 20.9%; Argon - 0.9%; Carbon dioxide, methane, inert gases - 0.1%.

Answer: elements

While elements have 'symbols' to denote them, compounds have 'formulae' which show the presence of more than one element, such as 'H20' for water, 'NaCl' for common salt, etc.

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Hope playing this quiz has been a fun and enlightening experience!