Formation of Complexes

Q. The increased tendency for complex formation in transition metals can be attributed to

1. Small size of the cations
2. High effective nuclear charge
3. Availability of low-energy vacant orbitals
4. All of these

Q. Read the assertion and reason carefully to mark the correct option out of the options given below:

(a)If both assertion and reason are true and the reason is the correct explanation of the assertion.

(b)If both assertion and reason are true but reason is not the correct explanation of the assertion.

(c)If assertion is true but reason is false.

(d) If assertion is false but reason is true.
Assertion : $N{a}_{2}C{r}_2{O}_7$ is not a primary standard solution in volumetric analysis.

Reason : $N{a}_{2}C{r}_2{O}_7$ is hygroscopic.

1. a
2. b
3. c
4. d

Q. The coinage metals are

1. Iron, Cobalt, Nickel
2. Copper and Zinc
3. Copper, Silver, Gold
4. Gold, Platinum

Q.

Name the following.

A non-metal essential for respiration and combustion

Q. Read the assertion and reason carefully to mark the correct option out of the options given below:

(a)If both assertion and reason are true and the reason is the correct explanation of the assertion.

(b)If both assertion and reason are true but reason is not the correct explanation of the assertion.

(c)If assertion is true but reason is false.

(d) If assertion is false but reason is true.
Assertion : $N{a}_{2}C{r}_2{O}_7$ is not a primary standard solution in volumetric analysis.

Reason : $N{a}_{2}C{r}_2{O}_7$ is hygroscopic.

1. a
2. b
3. c
4. d

Q. Which of the following metal is present in misch metal

1. La
2. Sc
3. Ni
4. Cr

Q. The increased tendency for complex formation in transition metals can be attributed to

1. Small size of the cations
2. High effective nuclear charge
3. Availability of low-energy vacant orbitals
4. All of these

Q. The tendency towards complex formation is maximum in

1. s-block elements
2. p-block elements
3. d-block elements
4. f-block elements

Q. In the dichromate dianion:

1. Four $Cr-O$ bonds are equivalent
2. Six $Cr-O$ bonds are equivalent
3. All $Cr-O$ bonds are equivalent
4. Three $Cr-O$ bonds are equivalent

Q. An alcoholic solution of dimethylglyoxime is added to an aqueous solution of nickel(II) chloride. Slow addition of ammonium hydroxide led to the precipitation of a bright-red coloured metal complex. The number of hydrogen bonds present in the structure of the complex are:

1. 6
2. \N
3. 2
4. 4

Q. In Nessler’s reagent for detection of $N{H}_3$, the active species is

1. $HgC{l}_2$
2. $H{g}^{2+}$
3. $H{g}_2{l}_2$
4. $Hg{l}_4^{2-}$

Q. Which of the following is a characteristic difference between lanthanoids and actinoids?

1. Reducing property

2. Oxidation state of +3

3. ionic radii trend of tripositive cations

4. Complex formation tendency

Q. When excess of $N{a}_2{S}_2{O}_3$ is added to dil.$AgN{O}_3$, a soluble compound ‘X’ is formed. However, when dil. $N{a}_2{S}_2{O}_3$ is added to conc. $AgN{O}_3$ solution, a white precipitate turns yellow and finally black. Precipitate ‘Y’ is formed here. Which is the correct pair?

1. ‘X’ is $A{g}_{2}S$ and ‘Y’ is $N{a}_3\left[Ag\right(S_2{O}_3{)}_2]$
2. ‘X’ is $N{a}_3\left[Ag\right(S_2{O}_3{)}_2]$ and ‘Y’ is $A{g}_{2}S$
3. ‘X’ is $A{g}_2{S}_2{O}_3$ and ‘Y’ is $A{g}_{2}S$
4. ‘X’ is $A{g}_2{S}_2{O}_3$ and ‘Y’ is $N{a}_3\left[Ag\right(S_2{O}_3{)}_2]$

Q. Bullet proof steel alloy is prepared by using

1. Sc
2. Ni
3. Zn
4. Cn

Q. What is the shape of the complex formed when dimethyl glyoxime reacts with $N{i}^{+2}$ion?

1. Trigonal bipyramidal
2. Octahedral
3. Square planar
4. Tetrahedral

Q. The coinage metals are

1. Iron, Cobalt, Nickel
2. Copper and Zinc
3. Copper, Silver, Gold
4. Gold, Platinum