p-Block Elements · JEE Main previous year questions

2023 27 questions

1. Q782023 · 24 Jan 2023 · Shift 1

   Reaction of $\mathrm{BeO}$ with ammonia and hydrogen fluoride gives A which on thermal decomposition gives $\mathrm{Be}{\mathrm{F}}_2$ and $\mathrm{N}{\mathrm{H}}_4\mathrm{F}$. What is 'A'?

   1. A.$(\mathrm{N}{\mathrm{H}}_4)\mathrm{B}{\mathrm{e}}_2{\mathrm{F}}_5$
   2. B.$(\mathrm{N}{\mathrm{H}}_4{)}_2\mathrm{Be}{\mathrm{F}}_4$
   3. C.$(\mathrm{N}{\mathrm{H}}_4)\mathrm{Be}{\mathrm{F}}_3$
   4. D.${\mathrm{H}}_3\mathrm{NBe}{\mathrm{F}}_3$
   Show answer

   Answer: B

2. Q802023 · 24 Jan 2023 · Shift 1

   Which of the Phosphorus oxoacid can create silver mirror from $\mathrm{AgN}{\mathrm{O}}_3$ solution?

   1. A.${\mathrm{H}}_4{\mathrm{P}}_2{\mathrm{O}}_5$
   2. B.${\mathrm{H}}_4{\mathrm{P}}_2{\mathrm{O}}_7$
   3. C.$(\mathrm{HP}{\mathrm{O}}_3{)}_{\mathrm{n}}$
   4. D.${\mathrm{H}}_4{\mathrm{P}}_2{\mathrm{O}}_6$
   Show answer

   Answer: A