Question

please answer these questions

Answer 1

d) we apply oil on iron tools because in direct contact of oxygen they start to get rust

e)it is stored in karosene because it reacts with water and air

Answer 2

1)(a)Carat is a measure of purity of gold, 24 carat considered the purest. In its purest form, gold is very soft and susceptible to dents and scratches. Hence, metals such as copper or silver are commonly added to make an alloy with gold to strengthen it.

(b)Although calcium is the fifth most abundant element in the earth's crust, it is never found free in nature since it easily forms compounds by reacting with oxygen and water. ... Calciumcarbonate (CaCO3) is one of the common compounds of calcium.

(c)Most electrical wire is covered in a rubber or plastic coating called insulation. ... The purpose of insulationcovering the metal part of an electrical wire is to prevent accidental contact with other conductors of electricity, which might result in an unintentionalelectric current through those other conductors.

(d) We oli the iron tools stored to prevent it from rusting.

(e)Sodium is a very reactive metal. It iskept in kerosene to prevent it from coming in contact with oxygen and moisture. If this happens, it will react with the moisture present in air and form sodium hydroxide. This is a strongly exothermic reaction, and lot of heat is generated.