NCERT MCQ CLASS-12 CHAPTER-8 | CHEMISTRY NCERT MCQ | THE d AND f-BLOCK ELEMENTS | EDUGROWN

In This Post we are  providing Chapter-8 The d and f-Block Elements NCERT MCQ for Class 12 Chemistry which will be beneficial for students. These solutions are updated according to 2021-22 syllabus. These MCQS  can be really helpful in the preparation of Board exams and will provide you with a brief knowledge of the chapter.

NCERT MCQ ON THE d AND f-BLOCK ELEMENTS

Question 1.
Oxidation number of gold metal is
(a) +1
(b) 0
(c) -1
(d) all of these

Answer: (a) +1

Question 2.
Shape of d-orbital is
(a) spherical
(b) dumb bell
(c) double dumb bell
(d) none of these

Answer: (c) double dumb bell

Question 3.
Electronic configuration of alkaline earth element is
(a) ns²
(b) ns¹
(c) np⁶
(d) ns⁰

Answer: (a) ns²

Question 4.
Lanthanoid contraction is due to increase in
(a) atomic number
(b) effective nuclear charge
(c) atomic radius
(d) valence electrons

Answer: (b) effective nuclear charge

Question 5.
Which one of the following is called green vitriol?
(a) FeSO₄ 7H₂O
(b) CuSO₄ 5H₂O
(c) CaSO₄ 2H₂O
(d) None of these

Answer: (a) FeSO₄ 7H₂O

Question 6.
Which block of elements are known as transition elements?
(a) p-block
(b) s-block
(c) d-block
(d) f-block

Answer: (c) d-block

Question 7.
Most abundant element in earth’s crust is
(a) Si
(b) Al
(c) Zn
(d) Fe

Answer: (a) Si

Question 8.
Which one of the following is diamagnetic ion?
(a) Co²⁺
(b) Ni²⁺
(c) Cu²⁺
(d) Zn²⁺

Answer: (d) Zn²⁺

Question 9.
Which of the following is not an element of first transition series?
(a) Iron
(b) Chromium
(c) Magnesium
(d) Nickel

Answer: (c) Magnesium

Question 10.
The correct order of EM2+/M0 values with negative sign for the four successive elements Cr, Mn, Fe and Co is
(a) Fe > Mn > Cr > Co
(b) Cr > Mn > Fe > Co
(c) Mn > Cr > Fe > Co
(d) Cr > Fe > Mn > Co

Answer: (c) Mn > Cr > Fe > Co

Question 11.
The number of unpaired electrons in gaseous species of Mn³⁺, Cl³⁺ and V³⁺ respectively are and the most stable species is
(a) 4, 3 and 2; V³⁺
(b) 3, 3 and 2; Cr³⁺
(c) 4, 3 and 2; Cr³⁺
(d) 3, 3 and 3; Mn³⁺

Answer: (c) 4, 3 and 2; Cr³⁺

Question 12.
Fe³⁺ ion is more stable than Fe²⁺ ion because
(a) more the charge on the atom, more is its stability
(b) configuration of Fe²⁺ is 3d⁵ while Fe³⁺ is 3d⁵
(c) Fe²⁺ has a larger size than Fe³⁺
(d) Fe³⁺ ions are colored hence more stable

Answer: (b) configuration of Fe²⁺ is 3d⁵ while Fe³⁺ is 3d⁵

Question 13.
Color of transition metal ions are due to absorption of some wavelength. This results in
(a) d-s transition
(b) s-s transition
(c) s-t/transition
(d) d-d transition

Answer: (d) d-d transition

Question 14.
Which group contains colored ions out of the following?
1. Cu^–. 2. Ti^4- 3. Co²⁺ 4. Fe^2-
(a) 1, 2, 3, 4
(b) 3, 4
(c) 2, 3
(4) 1, 2

Answer: (b) 3, 4

Question 15.
The melting points of Cu, Ag and Au follow the order
(a) Cu > Ag > Au
(b) Cu >Au > Ag
(c) Au > Ag > Cu
(d) Ag > Au > Cu

Answer: (b) Cu >Au > Ag

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