Question

A student learns that sodium and magnesium react with chloride to form sodium chloride and magnesium chloride, as shown. 2Na + Cl2 → 2NaCl ; Mg + Cl2 → MgCl2 The melting point of sodium chloride is 1074 K while the melting point of magnesium chloride is 981 K. Why does sodium chloride and magnesium chloride have a difference in melting point? a) Magnesium chloride is soluble in kerosene and petrol. b) Sodium chloride is formed by combining one atom of sodium with one molecule of chlorine. c) Sodium chloride has strong inter-ionic bonding than magnesium chloride. d) Magnesium chloride is formed by combining only one atom of magnesium and one molecule chlorine

Answer 1

Answer:

c) Sodium chloride has strong inter-ionic bonding than magnesium chloride

Explanation:

This is because the bonds that exist between sodium and chloride, and magnesium and chloride are not entirely ionic and some degree of covalency exists.

These factors combine to result in a higher force of attraction in sodium chloride as compared to magnesium chloride and hence a higher melting point for the former.

Answer 2

• From the given question the correct option is c.

• As we know that Both chlorides are ionic solids.

• The bonds that exist between both sodium chloride and magnesium chloride are not entirely ionic.

• As we know as compared to sodium, magnesium is more electronegative.  

• Hence there is a higher force of attraction in sodium chloride as compared to magnesium chloride.

• Due to strong inter-ionic bonding in sodium chloride than magnesium chloride,  both have a difference in melting point.