Oxides of Phosphorus

Q. White phosphorus burns in a limited supply of air to form Phosphorus trioxide. When this soft white solid is burnt in plentiful supply of air, we get phosphorus __.

Q. $P_2{O}_3,P_2{O}_{4}and{P}_2{O}_5$ exist as dimers.

1. True
2. False

Q. In which compound synergic effect is present?

1. $\left[Mn\right(H_{2}O{)}_6{]}^{2+}$
2. $[CuC{l}_4{]}^{2-}$
3. $\left[Ni\right(CO{)}_4]$
4. $[NiC{l}_4{]}^{2-}$

Q. On hydrolysis of $P_4{O}_{10}$ with water we obtain:

1. $H_{3}P{O}_{3}andP{H}_3$
2. $H_{3}P{O}_{4}and{H}_{3}P{O}_3$
3. $H_{3}P{O}_4$ only
4. $H_4{P}_2{O}_{7}and{H}_2$

Q. White phosphorus burns in a limited supply of air to form a soft white solid. This solid is Phosphorus __.

Q. Consider the following two carbonyl compounds
$\left(i\right)\left[Tc\right(CO{)}_6{]}^{+}$ and $\left(ii\right)\left[Nb\right(CO{)}_6{]}^{-}$

Which of the following is correct?

1. Only (b) is correct
2. "$CO$" bond order is greater in $\left[Nb\right(CO{)}_6{]}^{-}$ than in $\left[Tc\right(CO{)}_6{]}^{+}$
3. Both (a) and (b) are correct
4. "$Nb-C$" bond order in $\left[Nb\right(CO{)}_6{]}^{-}$ is greater than "$Tc-C$" bond order in $\left[Tc\right(CO{)}_6{]}^{+}$

Q. Upon heating $KCl{O}_3$ in the presence of catalytic amount of $Mn{O}_2$, a gas W is formed. Excess amount of W reacts with white phosphorus to give X. The reaction of X with $HN{O}_3$ gives Y and Z.

W and X are, respectively

1. $O_3$ and $P_4{O}_6$
2. $O_2$ and $P_4{O}_6$
3. $O_2$ and $P_4{O}_{10}$
4. $O_3$ and $P_4{O}_{10}$

Q. Which of the following compounds has shortest $B-F$ bond length?

1. $B{F}_4^{-}$
2. $B{F}_3\leftarrow N{H}_3$
3. $B{F}_3$
4. $B{F}_3\leftarrow N(C{H}_3{)}_3$

Q. On hydrolysis of $P_4{O}_{10}$ with water we obtain:

1. $H_{3}P{O}_{3}andP{H}_3$
2. $H_{3}P{O}_{4}and{H}_{3}P{O}_3$
3. $H_{3}P{O}_4$ only
4. $H_4{P}_2{O}_{7}and{H}_2$

Q. Upon heating $KCl{O}_3$ in the presence of catalytic amount of $Mn{O}_2$, a gas W is formed. Excess amount of W reacts with white phosphorus to give X. The reaction of X with $HN{O}_3$ gives Y and Z.

W and X are, respectively

1. $O_3$ and $P_4{O}_6$
2. $O_2$ and $P_4{O}_6$
3. $O_2$ and $P_4{O}_{10}$
4. $O_3$ and $P_4{O}_{10}$

Q. Phosphorus forms oxides such that there are several (two or more) P:O ratios possible - True or false?

1. True
2. False

Q. $P_4{O}_{10}$ is dimer of $P_2{O}_5$. The number of $P-P$ bond is/are.

1. zero
2. one
3. two
4. four