Chemistry Quiz 6

A limnic eruption (lake overturn) is a natural disaster in which dissolved carbon dioxide suddenly erupts from deep lake waters, forming a gas cloud capable of suffocating wildlife, livestock, and humans.

Litmus is a water-soluble mixture of different dyes obtained from lichens. It is often absorbed onto filter paper to produce one of the oldest forms of pH indicator, used to test materials for acidity.

The fuel used in an atomic reactor is Uranium. Uranium is the most widely used fuel by nuclear power plants for nuclear fission.

Ozone consists of oxygen only. It is a triatomic, molecule, consisting of three oxygen atoms. The formula for ozone is O₃. Ozone in the upper atmosphere protects living organisms by preventing damaging ultraviolet light from reaching the Earth's surface.

Uranium-235 (²³⁵U) is only found in about 0.7 percent of uranium found naturally, but it is well-suited for producing nuclear power. This is because it decays naturally by a process known as alpha radiation. This means that it releases an alpha particle (two neutrons and two protons connected together).

When formaldehyde and potassium hydroxide (KOH) are heated, we get methyl alcohol and potassium formate. This reaction is known as the Cannizzaro reaction. In Cannizzaro's reaction, one substance is oxidized and the other is reduced.

2HCHO+KOH → HCOOK+CH₃OH.
Thus in this reaction, methyl alcohol (CH₃OH) is produced. This reaction is known as Cannizaro's reaction

Ammonium sulphate ((NH₄)₂SO₄) is an inorganic salt with a number of commercial uses. The most common use is as a soil fertilizer since the chemical contains 21% nitrogen and 24% sulphur.

White phosphorus is a highly reactive clement. It is stored underwater for safekeeping to prevent it from catching fire spontaneously in the air. Red phosphorus is more stable than white phosphorus.

The reduction of a metal oxide to form metal by using aluminium powder as a reducing agent is called a thermite reaction. It is an exothermic reaction in which a large amount of heat is evolved. This reduction property of aluminium is used in welding broken pieces of iron rails and machine parts.

Cobalt oxide (Co₃O₄) imparts a deep blue colour to the glass. Before the glass can cool and solidify, cobalt can be added to the mixture to give the glass a deep blue colour.