Question

Name a non-metal having a very high melting point.

Answer 1

We know that by a nonmetal, we know that an element that doesn't fall into alkali, alkaline earth, transition metal, post transition metals, actinides. Whenever the secondly by having the high melting point we are going to assume we have melting points that are high when compared with metals. Using the provided definition, we have boron satisfy the criteria. We get the Boron which is basically classified into metalloid as it has a higher melting point than all of the 8 elements.

Complete answer:
For this question, mostly we all go with carbon but we have to analyze it and whose sublimation is the temperature which is higher than the melting point of all other elements. However it needs to be pointed that carbon rich compounds don’t melt at the given temperature which under a standard pressure that they go directly from solid to gas phase sublimation.

So in short the temperature is not the melting point. In order to melt carbon-rich compounds like graphite or we can say diamond we need to subject it to enormous pressure and bring temperature up to sublimation point and also keep it in an inert atmosphere then they will melt.

Also Diamond and Graphite have more and more melting and boiling point because they are the substances with giant covalent structures that have very high melting points, because a lot of strong covalent bonds must be broken.

Note: Note that at the standard pressure condition and the carbon which sublimes directly into solid form into gaseous at $3900K$ which is around $\left( 3627\text{ }C \right)$ Remember this only happen in carbon arc electrode. At higher pressure of $100$ atmosphere carbon will be more liquidity at $4500K$ likely some liquid carbon in the Earth’s core where pressure is much high than $100atm$ and temperature over $6000~K$