Question

Why do goldsmiths use outermost flame to burn gold and silver?

Answer 1

Hint: Gold and silver are metals and we know that the melting point and boiling point of metal is high. So we need high energy or heat to melt or boil these metals. They also have high densities.

Complete step by step solution:
First of all we will talk about metals, non-metals and their properties.
Elements: A substance which cannot be broken down further by chemical and physical method, is called an element. They are made up of atoms. All the atoms in an element are of the same kind.
Elements are classified into two categories:
Metals and Non-metals

Metals	Non-metals
They are solid at room temperature.	They may be solid, liquid and gas at room temperature.
They have high melting and boiling points.	They have low melting and boiling points.
They are good conductors of heat and electricity.	They are bad conductors of heat and electricity.
They are ductile (which can be drawn into wires).	They are non-ductile.
They are malleable (which can be drawn into thin sheets)	They are non-malleable.

Metalloids: The elements which show the properties of both i.e. metals as well as non-metals, are known as metalloids.
Now the metals which are found in native state (which do not react with other elements) in nature are gold (Au), silver (Ag) and copper (Cu). They are found on the earth's crust and they are native in nature. They are collectively known as coinage metals. They are native in nature because they do not react with most of the substance. Due to their native property these metals are used to make jewellery and coins.
Goldsmiths use outermost flame to burn gold and silver because they have high melting points. The heat in the outermost part of the flame is highest. This large heat helps these metals melt easily.
So, goldsmiths use outermost flame to burn gold and silver.

Note: There are so many exceptions for the physical properties of metals and non-metals. For example: generally metals are hard to cut but sodium and potassium are very soft that they can be cut by knife. Generally non-metals are light but diamond is the hardest substance which is known to us.