Atomic and Ionic Sizes of Lanthanides

Q. Correct order of boling point of d-block series of corresponding elements is

1. 3d > 4d > 5d
2. 3d < 4d < 5d
3. 3d > 4d $\approx$ 5d
4. 3d < 4d $\approx$ 5d

Q. Arrange the $C{e}^{+3},L{a}^{+3},P{m}^{+3}andY{b}^{+3}$ in increasing order of their ionic radii:

1. $Y{b}^{+3}<P{m}^{+3}<C{e}^{+3}<L{a}^{+3}$
2. $C{e}^{+3}<Y{b}^{+3}<P{m}^{+3}<L{a}^{+3}$
3. $Y{b}^{+3}<P{m}^{+3}<L{a}^{+3}<C{e}^{+3}$
4. $P{m}^{+3}<L{a}^{+3}<C{e}^{+3}<Y{b}^{+3}$

Q. Minimum ionic radii among the following is of

1. $C{e}^{3+}$
2. $P{r}^{3+}$
3. $S{m}^{3+}$
4. $E{u}^{3+}$

Q. Which of the following orders regarding melting point of lithium halides is true

1. LiI < LiBr < LiCl < LiF
2. LiCl > LiI > LiBr > LiF
3. LiF > LiCl > LiF > LiBr
4. LiI > LiBr > LiCl > LiF

Q. Because of lanthanoid contraction, which of the following pairs of elements have nearly same atomic radii? (Numbers in the parenthesis are atomic numbers)

1. Zr(40) and Ta(73)
2. Ti(22) and Zr(40)
3. Zr(40) and Nb (41)
4. Zr(40) and Hf(72)

Q. Which of the following statement is true with respect to 3d series?

1. Atomic radii gradually decreases from Sc to Zn.
2. Most of these elements have very similar atomic radii. There is hardly any appreciable variation.
3. Atomic radii gradually decreases from Sc to Cr.
4. Atomic radii gradually increases from Sc to Cr.

Q. Which of the following statement is correct about $CsB{r}_3$?

1. It contains $C{s}^{+}$ and $B{r}_3^{-}$ ions
2. It is a covalent compound
3. It contains $C{s}^{+}$ and $B{r}^{3-}$ ions
4. It contains $C{s}^{3+}$ and $B{r}^{-}$ ions

Q. Identify the incorrect statement among the following:

1. d-block elements show irregular and erratic chemical properties among themselves
2. The chemistry of various lanthanoids are very similar
3. La and Lu have partially filled d orbitals only
4. 4f and 5f orbitals are equally shielded

Q. What is the order of melting point of elements of alkaline Earth elements

Q.

Which is the last member of the Lanthanide series?

Q. Which graph shows the correct trends for the size of $L{n}^{3+}$ ions?

1. 
2. 
3. 
4. 

Q. The separation of Lanthanides by ion exchange method is based on:

1. basicity of the hydroxides
2. size of the ions
3. the solubility of their nitrates
4. oxidation state of the ion.

Q. Boiling and melting point of Zn, Hg and Cd are low due to

1. partially filled d-orbital
2. absence of unpaired electrons
3. poor shielding of d-orbital
4. higher nuclear charge

Q.

Name the members of the lanthanoid series which exhibit +4 oxidation state and those which exhibit +2 oxidation state. Try to correlate this type of behavior with the electronic configurations of these elements.

Q. What is lanthanide contraction? Explain the cause of lanthanide contraction.

Q. Reason of lanthanoid contraction is- (1) Negligible screening effect of f orbitals (2) Increasing nuclear charge (3) Decreasing nuclear charge (4) Decreasing screening effect Explain between option 1 and 4

Q.

Lanthanoid contraction is observed in:

1. d- block elements

2. p- block elements

3. s-block elements

4. f- block elements

Q.

Assertion: Along a period, atomic size of the elements increases.

Reason: In a particular, no new shells is formed and electrons are filled in the same shell.

Mark the correct choice

1. Both assertion and reason are correct and the reason is the correct explanation of assertion.

2. Both assertion and reason are correct but the reason is not the correct explanation of assertion.

3. Assertion is correct but the reason is incorrect.

4. Assertion is incorrect but reason is correct.

Q.

On moving from left to right in a period in the periodic table, the size of the atom.

1. Increases

2. Decreases

3. Does not change appreciably

4. First decreases and then increases

Q. What is meant by Lanthanide contraction? Write the general electronic configuration of inner transition elements.

Q. What is lanthanide contraction? Mention the cause for it.

Q.

Choose incorrect option:-
1. Transition elements exhibit higher enthalpies of atomization.
2. Zinc is a transition element
3. Melting and boiling points increases steadily from Sc to Cu.

1. 1 & 2
2. 2&3
3. 1, 2 & 3
4. 3 only.

Q.

Which ion will show more paramagnetic behaviour ?

1. Fe ²⁺

2. Cu⁺

3. Fe ³⁺

4. Ag⁺

Q.

In nitrogen, aluminium, oxygen, calcium the correct order of

Paramagnetism is? And why....

Q. What is lanthanide contraction and its causes ?

Q. The total number of atomic orbitals in fourth energy level of an atom is

1. $8$
2. $16$
3. $32$
4. $4$

Q.

Which is the smallest atom?

Q.

What is fusion?

Q.

Which one of S, P, Ca, Si would yield a basic oxide?

Q. Identify the incorrect statement among the following:

1. d-block elements show irregular and erratic chemical properties among themselves
2. La and Lu have partially filled d orbitals only
3. The chemistry of various lanthanoids are very similar
4. 4f and 5f orbitals are equally shielded