Question

On the basis of structure, which of the following solids has the highest melting point? Question 4 options: sucrose ,table salt ,glucose , or butter

Answer 1

Answer: Table salt

Explanation: Sucrose $C_{12}H_{22}O_{11}$ is a covalent compound which is formed by sharing of electrons and thus form a weak bond.  

Table salt $NaCl$ is a ionic compound formed by transfer of electrons and thus a strong bond is formed due to strong coloumbic forces.Thus large amount of energy is required to break the bonds and they have high melting points.

Glucose  $C_6H_{12}O_6$ is a covalent compound which is formed by sharing of electrons and thus form a weak bond.  

Butter is also a covalent compound which is formed by sharing of electrons and thus form a weak bond.  

Answer 2

Answer:

Table salt (NaCl)

Explanation:

Of all the options, only one of the compounds has electrovalent intramolecular force of attraction which is NaCl. The remaining are organic compounds and the bond that exists within organic compounds (the carbon-carbon) are covalent bond. Electrovalent or ionic bonds are stronger than covalent bonds and this case is no exception. The melting point of NaCl is 801 oC while those of sucrose, glucose and butter are 186 oC, 146 oC and 35 oC respectively.

Compounds that are held together by electrovalent combinations are known as electrovalent/Ionic compounds.