Uses of Lanthanides

Q.

Give reasons:

Why copper is used to make hot water tanks and not steel (an alloy of iron).

Q.

Out of NH3, PH3, AsH3 and SbH3 the most basic hydride is______

Q.

Anion ${\mathrm{O}}^{-}$ is isoelectronic with_______.

Q. Consider the following compounds


Arrange these compounds in decreasing order of their basicity

1. II > III > I > IV
2. IV > I > III > II
3. I > II > III > IV
4. IV > I > II > III

Q.

Pitch-blende is the source of some metals. Find the total number of such metals among these: $\mathrm{Hg},\mathrm{Ra},\mathrm{U},\mathrm{Th},\mathrm{Zn},\mathrm{Tc}$

Q.

What do you understand about the term non-stoichiometric hydrides? Do you expect this type of hydride to be formed by alkali metals? Justify your answer.

Q. Which can be used for production of steel and stainless steel?

Q.

Which of the following group contain mostly radioactive elements ?

1. Halogens

2. Alkaline earth metals

3. Actinoids

4. Non metals

Q. Which transition metal is called wonder metal ?

1. $Sc$
2. $Ti$
3. $Fe$
4. $Mn$

Q. What is lanthanoid contraction

Q.

Why is Chromium used in stainless steel?

Q. Why Phosphorus pentachloride is more covalent than phosphorus trichloride?

Q. Choose the incorrect statement among the following:

1. the chemistry of different lanthanoids is very similar
2. $4f-$ and $5f-$ orbitals are equally shielded
3. $d-$block element show irregular and erratic chemical properties among themselves
4. $La$ and $Lu$ have partially filled d-orbitals

Q.

How many orbitals are filled in the second period?

Q.

Which of the following lanthanides is commonly used?

1. Lanthanum

2. Nobelium

3. Thorium

4. Cerium

Q. Identify X in the reaction below :

1. aldoxime
2. alkyl isonitrile
3. alkyl halide
4. alkane nitrile

Q.

Why is radium 226 unstable?

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

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

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

1. 
2. 
3. 
4. 

Q. In which of the following groups inert pair effect does not occur?

1. 13th
2. 14th
3. 15th
4. 16th

Q. Lanthanum is grouped with $f-$block elements because:

1. it has partially filled $f-$orbitals
2. it is just before $Ce$ in the periodic table
3. it has both partially filled $f$ and $d-$orbitals
4. the properties of Lanthanum are very similar to the elements of $4$f block

Q. The trend of basicity of lanthanoid hydroxides:

1. first increases and then decreases
2. increases across the lanthanoid series
3. decreases across the lanthanoid series
4. first decreases and then increases

Q. Consider the following statements in respect of lanthanoids.
1. The basic strength of hydroxides of lanthanoids increases from L$a(OH{)}_3$ to $Lu(OH{)}_4$.
2. The lanthanoid ions $L{u}^{3+},Yb62+,C{e}^{4+}$ are diamagnetic.
Which of the statement(s) given above is are correct?

1. Only 1
2. Only 2
3. Both 1 and 2
4. Neither 1 nor 2

Q.

How many coulombs are required for the oxidation of 1 mol of $H_{2}Oto{O}_2$?

1. $93000C$
2. $1.93\times {10}^{5}C$
3. $9.65\times {10}^{4}C$
4. $19.3\times {10}^{2}C$

Q.

The mineral that does not contain Magnesium is

1. Dolomite

2. Carnallite

3. Magnesite

4. Bauxite

Q. Ornamental gold is an alloy of gold and silver.

1. True
2. False

Q. Consider the following statements with respect to lanthanides:

1. Neither 1 nor 2
2. Both 1 and 2
3. 1 only
4. 2 only

Q. Which is the strongest base among the following?

1. $La(OH{)}_3$
2. $Lu(OH{)}_3$
3. $Ce(OH{)}_3$
4. $Yb(OH{)}_3$

Q. Across the lanthanide series, the basicity of the lanthanide hydroxides?

1. First decrease and then increase
2. Increases
3. Decreases
4. First increase and then decrease

Q. Lanthanides are extracted from:

1. Monazite
2. Limonite
3. Magnetite
4. Cassiterite