Sc (Z = 21) is a transition element but Zinc (z = 30) is not because _______.

(a)

both Sc³⁺ and Zn²⁺ ions are colourless and form white compounds

(b)

In case of Sc, 3d orbital are partially filled but in Zn these are completely filled

(c)

last electron as assumed to be added to 4s level in case of zinc

(d)

both Sc and Zn do not exhibit variable oxidation states

The correct order of increasing oxidizing power in the series _______.

(a)

VO₂⁺ < Cr₂O₇^2- < MnO₄^-

(b)

Cr₂O₇^2- < VO₂⁺ < MnO₄^-

(c)

Cr₂O₇^2- < MnO₄^- < VO₂⁺

(d)

MnO₄^- < Cr₂O₇^2- < VO₂⁺

The alloy of copper that contain Zinc is________.

(a)

Monel metal

(b)

Bronze

(c)

bell metal

(d)

brass

In acid medium, potassium permanganate oxidizes oxalic acid to _______.

(a)

oxalate

(b)

Carbon dioxide

(c)

acetate

(d)

acetic acid

Which of the following statements is not true?

(a)

on passing H₂S, through acidified K₂Cr₂O₇ solution, a milky colour is observed

(b)

Na₂Cr₂O₇ is preferred over K₂Cr₂O₇ in volumetric analysis

(c)

K₂Cr₂O₇ solution in acidic medium is orange in colour

(d)

K₂Cr₂O₇ solution becomes yellow on increasing the P^H beyond 7

Which of the following is wrong with respect to lanthanide contraction?

(a)

Decrease in ionic radii

(b)

Increase in tendency to act as reducing agents

(c)

Decrease in basic character

(d)

Resembles second and third row of d-block elements

Hybridisation of chromium ions and dichromate ions is ________.

(a)

Sp²

(b)

Sp³d

(c)

both (a) and (b)

(d)

None of these

The highest possible oxidation state shown by osmium in its compound is_______.

(a)

+4

(b)

+6

(c)

+8

(d)

+10

Identify the paramagnetic species.

(a)

Cu⁺

(b)

Cr⁺

(c)

MnO₄

(d)

Zn²⁺

The trend in ionisation enthalpy of a transition element is not regular because,_______.

(a)

removal of one electron alters the relative energies of 4s and 3d orbitals

(b)

due to different electronic configuration (stability)

(c)

Poor screening of 3p-orbital

(d)

due to decrease in effective nuclear charge

Oxocations

(1)

Monazite sand

Zr and Hf

(2)

Lanthanide-thermic process

Lanthanide

(3)

Rare earth elements

Metallothermic

(4)

Similar size

f - block elements

(5)

Actinides