Question

 

What does a melting range of 131°C-139°C indicate?

What is a “good” melting range?

 

Answer 1

A melting range of 131^oC- 139^oC means that a given solid will change its phase to liquid in this particular temperature range. It means that you keep heating the solid till its temperature increases to 131^oC. If we keep on heating it, the substance will melt in any temperature between 131^oC- 139^oC.

There's no good melting point. It depends on the substance. Melting point can be high or low. High melting point means that we will require more heat requried to melt that particular substance.

For example - Electrical wires are made of metals as they have high melting point. If we make wire using a substance having very low melting point then wire will melt if slightly high amount of current flows through it due to heat. On the other hand we do not want our wire to have very high melting point also as it will be able to withstand more than requried amount of current which might damage our equipment to which wire is connected. Fuse works on this principle. It protects electrical equipment from excessive current. If high current flows, the heating effect of current causes fuse wire to melt and no current flows to our equipment.