The d- and f- Block Elements Test

Result

The d- and f- Block Elements Test - 67

Score
-
out of -
Rank
-
out of -

TIME Taken - -

SHARING IS CARING

If our Website helped you a little, then kindly spread our voice using Social Networks. Spread our word to your readers, friends, teachers, students & all those close ones who deserve to know what you know now.

Weekly Quiz Competition

Question 1
1 / -0

Which of the pair of complex compounds are tetrahedral as well as diamagnetic?

A
$$[CoCl_4]^-$$ and $$[Co(CO)_4]^-$$

B
$$[Ag(SCN)_4]^{2-}$$ and $$[NiCl_4]^{2-}$$

C
$$[Co(CO)_4]^-$$ and $$[Ni(CN)_4]^{4-}$$

D
$$[PdCl_4]^{2-}$$ and $$[Ni(CN)_4]^{2-}$$

Solution
Question 2
1 / -0

Which of the following is incorrect about Wilkinson's catalyst?

A
It is a non-ionic complex

B
It is a diamagnetic complex

C
It is a tetrahedral complex

D
It is very effective for selective hydrogenation of organic molecule at room temperature and pressure

Solution
Question 3
1 / -0

The magnetic moment of a certain complex(A) of Co was found to be $$4.89$$ B.M. and the EAN as $$36$$. Co also forms complex(B) with magnetic moment $$3.87$$ B.M. and EAN $$37$$, and complex(C) with EAN as $$36$$ but diamagnetic. Which of the following statements is true regarding the above observation?

A
The oxidation states of Co in (A), (B) and (C) are $$+3, +2$$ and $$+3$$, respectively

B
Complexes (A) and (B) have $$sp^3d^2$$ hybridization state while (C) has $$dsp^3$$ hybridizaiton state

C
The spin multiplicities of Co in (A), (B) and (C) are $$4, 3$$ and $$1$$, respectively

D
The oxidation states of Co in (A), (B) and (C) are $$+6, +8$ and $$+1$$, respectively

Solution
Question 4
1 / -0

Which of the following complex is paramagnetic?

A
$$K_2[Ni(CN)_4]$$

B
$$K_4[Fe(CN)_6]$$

C
$$[Co(NH_3)_6]Cl_3$$

D
$$[Cr(H_2O)_6]SO_4$$

Solution

The electronic configurations of $$Ni, Fe, Co$$ and $$Cr$$ in the given complexes are $$(3d)^8, (3d)^6, (3d)^6$$ and $$(3d)^4$$, respectively.

These involve $$dsp^2, d^2sp^3, d^2sp^3$$ and $$sp^3d^2$$-hybridization, respectively.

The complex $$[Cr(H_2O)_6]SO_4$$ will be paramagnetic as Cr contains four unpaired electrons.
Question 5
1 / -0

If a transition-metal compound absorbs violet-indigo radiation in the visible region. Its color would be?

A
Green

B
Yellow

C
Orange

D
Blue

Solution

The correct answer is option B.By observing the colour absorption-emission chart we can sath that the colour opposite to the aborbed colour will be reflected and we will be able to see that reflected colour.Here Yellow colour radiation will be reflected when violet/indigo radiation is absorbed.
Question 6
1 / -0

Which of the following complexes has magnetic moment of $$2.83$$ Bohr magneton?

A
$$[Ni(NH_3)_6]^{2+}$$

B
$$[Ni(CN)_4]^{2-}$$

C
$$TiCl_4$$

D
$$[CoCl_6]^{3-}$$

Solution

$$2.83$$ Bohr magneton implies two unpaired electrons according to the expression $$\sqrt{n(n+2)}$$B.M.

The species $$Cu, Ni, Ti$$ and $$Co$$ in the given complexes have $$(3d)^8, (3d)^8, (3d)^0$$, and $$(3d)^6$$ electronic configurations, respectively.

These involve $$sp^3 d^2, dsp^2, sp^3$$ and $$sp^3d^2$$ hybridization, respectively.

Thus, the complex $$[Ni(NH_3)_6]^{2+}$$ has two unpaired electrons.
Question 7
1 / -0

Among the following ions which one has the highest paramagnesium?

A
$$[Cr(H_2O)_6]^{3+}$$

B
$$[Fe(H_2O)_6]^{2+}$$

C
$$[Cu(H_2O)_6]^{2+}$$

D
$$[Zn(H_2O)_6[^{2+}$$

Solution
Question 8
1 / -0

Which of the following anion exists in equilibrium condition with other anion depending upon the pH of the solution?

A
$$ CrO^{2-}_{4} $$

B
$$ SO^{2-}_{4} $$

C
$$ CO^{2-}_{3} $$

D
$$ SO^{2-}_{3}$$
Question 9
1 / -0

$$ Cr_2O^{2-}_7 \rightarrow{H^+} +Cr^{3+}.\ Eq.wt.of Cr_2O_7^{2-} $$ is

A
mol.wt/6

B
mol wt./3

C
mol. wt/4

D
mol. wt/1

Solution
Question 10
1 / -0

Which of the following sulphide is yellow in colour?

A
$$CuS$$

B
$$CdS$$

C
$$ZnS$$

D
$$CoS$$

Solution

CdS is a yellow coloured ppt.
CoS and CuS are black, while ZnS is white.
Hence, option B is correct.