Question

The following are some statements related to $VA$ group hydrides, I. Reducing property increases from $NH_{3}$ to $BiH_{3}$ II. Tendency to donate lone pair decreases from $NH_{3}$ to $BiH_{3}$ III. Thermal stability of hydrides decreases from $NH_{3}$ to $BiH_{3}$ IV. Bond angle of hydrides decreases from $NH_{3}$ to $BiH_{3}$ The correct statements are

• A. I, II, III and IV
• B. I, III and IV
• C. I, II and IV
• D. I and IV

Answer 1

Answer: (A)

I, II, III and IV

Answer 2

(I) The reducing property of the hydrides of $VA$ group increases from $NH _{3}$ to $BiH _{3}$ as $M- H$ bond length increases. (Where, $M=N$, $P$ As, $Sb , Bi$ ) $NH _{3}< PH _{3}< AsH _{3}< SbH _{3}< BiH _{3}$ (II) The tendency to donate lone pair or basic strength decreases from $NH _{3}$ to $BiH _{3}$. $NH _{3}> PH _{3}> AsH _{3}> SbH _{3}> BiH _{3}$ (III) Thermal stability of VA group hydrides decreases from $NH _{3}$ to $BiH _{3}$. $NH _{3}> PH _{3}> AsH _{3}> SbH _{3}> BiH _{3}$ (IV) Bond angle of VA group hydrides decreases from $NH _{3}$ to $BiH _{3}$ $NH _{3}> PH _{3}> AsH _{3}> SbH _{3}> BiH _{3}$