Coordination and Oxidation Number

Q. If a solid OQ having NaCl structure is heated so that the ions along one body diagonal are lost and trivalent ions R enter interstitial sites to maintain electrical neutrality so that new empirical formula unit is PxQyRz (x, y, z are smallest possible integers). The value of x+y+z is

Q. Which of the following oxoacid of sulphur has $S-O-S$ linkage?

1. Sulphurous acid
2. Sulphuric acid
3. Pyrosulphuric acid
4. Peroxy-disulphuric acid

Q. The number of second nearest Na+ ions neighbour of a Na+ ion in NaCl structure is

Q. What is the magnetic moment (spin only) and hybridization of central atom in the brown ring complex $\left[Fe\right(H_{2}O{)}_{5}NO]S{O}_4?$

1. $\sqrt{3}B.M,d^{2}s{p}^3$
2. $\sqrt{3}B.M,s{p}^3{d}^2$
3. $\sqrt{15}B.M.,s{p}^3{d}^2$
4. $\sqrt{15}B.M.,d^{2}s{p}^3$

Q. An element has a face centered cubic (fcc) structure with a cell edge of $200\text{pm}$. The atomic radius is:

1. $\frac{\sqrt{3}}{2}\times 200\text{pm}$
2. $\frac{1}{\sqrt{2}}\times 200\text{pm}$
3. $\frac{1}{2\sqrt{2}}\times 200\text{pm}$
4. $\frac{2}{\sqrt{3}}\times 200\text{pm}$

Q. The number of unpaired electrons in the complex ion $[Co{F}_6{]}^{3-}$ is
(Atomic number Co=27)

1. 4
2. 0
3. 2
4. 3

Q. In solid $AB,B^{-}$ forms the fcc lattice and $A^{+}$ occupies all the octahedral voids. If atoms from the edge centers along an axis connecting the opposite edge centers on a same face are removed, what will be the empirical formula of the compound?

1. $A_8{B}_5$
2. $A_7{B}_8$
3. $A_8{B}_5$
4. $A_3{B}_8$

Q.

Give the oxidation state, d-orbital occupation and coordination number of the central metal ion in the following complexes:
$K_3\left[Co\right(C_2{O}_4{)}_3]$

$\left(N{H}_4{)}_2\right[Co{F}_4]$

$Cis-\left[Cr\right(en{)}_{2}C{l}_2]Cl$

$\left[Mn\right(H_{2}O{)}_6]S{O}_4$

Q. In the $ZnS$ (Zinc Blende) structure, what would be the distance for the nearest cation $\left(Z{n}^{2+}\right)$ from an anion $\left(S^{2-}\right)$ ?
Here $a$ is the edge cell length.

1. $\frac{\sqrt{3}a}{4}$
2. $\sqrt{2}a$
3. $\frac{a}{4}$
4. $a$

Q. Which of the following statements is/are true regarding $L{i}_{2}O$ (anti-fluorite structure) ?

1. $r_{L{i}^{+}}+r_{O^{2-}}=\frac{\sqrt{3}a}{4}$
2. oxide ions forms the fcc lattice
3. cations are present in all the tetrahedral voids
4. All of the above

Q. In the $NaCl$ (Rock salt) structure, what would be the distance for the nearest cation $\left(N{a}^{+}\right)$ from an anion $\left(C{l}^{-}\right)$ ?
Here $a$ is the edge cell length.

1. $\frac{a}{4}$
2. $\frac{a}{2}$
3. $\frac{a}{\sqrt{2}}$
4. $a$

Q. Choose the correct statement regarding $\left[Ni\right(CO{)}_4]$:

1. $\left[Ni\right(CO{)}_4]$ is diamagnetic and tetrahedral
2. $\left[Ni\right(CO{)}_4]$ is paramagnetic and tetrahedral
3. $\left[Ni\right(CO{)}_4]$ is diamagnetic and square planar
4. $\left[Ni\right(CO{)}_4]$ is paramagnetic and square planar

Q.

Fluorine reacts with water to give ?

1. hydrogen fluoride and oxygen

2. hydrogen fluoride and ozone

3. hydrogen fluoride and oxygen fluoride

4. hydrogen fluoride, oxygen and ozone

Q.

When
$1molCrC{l}_3.6H_{2}O$ is treated with excess of $AgN{O}_3,3\text{mol of}AgCl$ are obtained. The formula of the complex is:

1. $\left[CrC{l}_3\right(H_{2}O{)}_4]Cl.2H_{2}O$
2. $\left[CrCl\right(H_{2}O{)}_5]C{l}_2.H_{2}O$
3. $\left[Cr\right(H_{2}O{)}_6]C{l}_3$
4. $\left[CrC{l}_3\right(H_{2}O{)}_3].3H_{2}O$

Q. Which of the following is correct relation between radius of octahedral void (r) and radius of atom (R) in closed packed structure?

1. $R=0.732r$
2. $r=0.732R$
3. $R=0.414r$
4. $r=0.414R$

Q. Choose the correct statement(s).
I. The geometry of $Ni(CO{)}_4$ and $Ni(PP{h}_3{)}_{2}C{l}_2$ are tetrahedral.
II. $K_2\left[Pt\right(CN{)}_4]$ and $N{a}_3\left[Co\right(C_2{O}_4{)}_3]$ are diamagnetic.
III. All the geometrical isomers of $\left[M\right(AB\left)b_{2}cd\right]$ are optically active.

1. I only
2. I and II
3. III only
4. All of these

Q.

What is formed when potassium is heated strongly in oxygen?

Q.

Specify the oxidation numbers of the metals in the following coordination entities:
(i) ${\left[Co\left(H_{2}O\right)\left(CN\right)\right(en{)}_2]}^{2+}$

(ii) $K_3\left[Fe{\left(CN\right)}_6\right]$

(iii) ${\left[CoB{r}_2{\left(en\right)}_2\right]}^{+}$

(iv) $\left[Cr{\left(N{H}_3\right)}_{3}C{l}_3\right]$

(v) ${\left[PtC{l}_4\right]}^{2-}$

Q. Identify the correct statement from the following.
(a) On commercial scale, $C{O}_2$ is obtained by heating limestone.
(b) Graphite is used as a dry lubricant.
(c) $Si{O}_2$ reacts with $HF$ but does not react with $NaOH$.
(d) In $[GeC{l}_6{]}^{2–}$, the hybridisation of central atom is $s{p}^3{d}^2$.

1. (a) and (b) only
2. (b) and (c) only
3. (b) and (d) only
4. (a), (b) and (d) only

Q. Will all central metal atom in coordination complex be cation in coordination complex?!? if so Why should it have that charge???

Q.

Which of the following option are correct for $\left[Fe\right(CN{)}_6{]}^{3-}$ complex?
(a) $d^{2}s{p}^3$ hybridisation
(b) $s{p}^3{d}^2$ hybridisation
(c) Paramagnetic
(d) Diamagnetic

Q. The coordination no. of copper in cuprammonium sulphate is

1. 6
2. 4
3. 8
4. 2

Q. The correct order of the stoichiometries of $AgCl$ formed when $AgN{O}_3$ in excess is treated with the complexes : $CoC{l}_3.6N{H}_3,CoC{l}_3.5N{H}_3,CoC{l}_3.4N{H}_3$ respectively is:

1. $1AgCl,3AgCl,2AgCl$
2. $3AgCl,1AgCl,2AgCl$
3. $3AgCl,2AgCl,1AgCl$
4. $2AgCl,3AgCl,1AgCl$

Q. The charge on the central metal ion in the complex $\left[Ni\right(CO{)}_4]$ is

1. 2
2. 4
3. 0
4. 3

Q. The coordination number and oxidation number of X in the following compound is : $\left[X\right(S{O}_4\left)\right(N{H}_3{)}_5]Cl$

1. 10, 3
2. 2, 6
3. 6, 3
4. 6, 4

Q. In which of the following complexes, nickel is in the highest oxidation state?

1. $K_4\left[Ni\right(CN{)}_4]$
2. $\left[Ni\right(CN{)}_4{]}^{2-}$
3. $\left[K_{2}Ni{F}_6\right]$
4. $\left[Ni\right(CO{)}_4]$

Q. Consider the following and choose the correct option.
Statement -1 :Both $\left[Co\right(ox{)}_3{]}^{3-}and[Co{F}_6{]}^{3-}$ are paramagnetic
Statement 2 :$CoC{l}_3.3N{H}_3$ complex is non conducting.
Statement 3 : The number of all possible isomers for the complex $\left[Pt\right(N{O}_2\left)\right(py\left)\right(OH\left)\right(N{H}_3\left)\right]$ is six
Statement 4: The oxidatation state of iron in brown ring complex $\left[Fe\right(H_{2}O{)}_{5}NO]S{O}_4$ is +2 where $NO$ is $N{O}^{+}$

1. FFTF
2. TTTF
3. FTFF
4. TTTT

Q. A mixture of mgcl2 and MgSo4 contains .6 moles of cl and .2 moles of sulphate ions. The equivalent fraction of Mg2+ present in the mixture is

Q. Why are $Cu,Ag$ and $Ag$ included under transition elements even though they contain completely filled $d-$orbitals in their ground state?

Q. A six-coordinate complex of formula $CrC{l}_6.6H_2$O is green in colour. A $0.1\text{M}$ solution of the complex when treated with excess of $AgN{O}_3$ gave $28.7\text{g}$ of white precipitate. The formula of the complex would be:

1. $\left[Cr\right(H_{2}O{)}_{4}C{l}_2]Cl.2H_{2}O$
2. $\left[Cr{\left(H_{2}O\right)}_6\right]C{l}_3$
3. $\left[Cr{\left(H_{2}O\right)}_{5}Cl\right]C{l}_2.H_{2}O$
4. $\left[Cr{\left(H_{2}O\right)}_{3}C{l}_3\right].3H_{2}O$