DPP

In which of the following molecules, the octet rule is not obeyed?

Which of the following statements is/are correct regarding ionic compounds?

 In which of the following driving force is to complete the octet of $\mathrm{B}$ atom permanently?

The compound which contains both ionic and covalent bond is/are:

$\mathrm{A}, \mathrm{B}, \mathrm{C}$ are three substances. $\mathrm{A}$ does not conduct electricity in the solid or liquid state. $\mathrm{B}$ conducts electricity both in the fused and solution states, while $\mathrm{C}$ conducts electricity only in the solution state. Which of the following statement(s) is/are true regarding $\mathrm{A}, \mathrm{B}$ and $\mathrm{C}$?

Which contains both covalent and ionic bonds?

Which has a giant covalent structure?

Lattice energy of ${\mathrm{BeCO}}_3\left(\mathrm{I}\right), {\mathrm{MgCO}}_3\left(\mathrm{II}\right)$ and ${\mathrm{CaCO}}_3\left(\mathrm{III}\right)$ is in order: