+91-8076753736 support@wiredfaculty.com

Sponsor Area

The D-And-f-Block Elements

Question

Wired Faculty App

What are alloys? Name an important alloy which contains some of the lanthanoid metals. Mention its uses.

Solution

An alloy is a blend of metals prepared by mixing the components. Alloys may be homogeneous solid solutions in which the atoms of one metal are distributed randomly among the atoms of the other. Such alloys are formed by atoms with metallic radii that are within about 15 percent of each other. Because of similar radii and other characteristics of transition metals, alloys are readily formed by these metals.

An important alloy which contains some of the lanthanoid is mischmetall. Mischmetall consists of a lanthanoid metal (~95%) and iron (~5%) and traces of S, C, Ca and Al.

Uses:
(i) Mischmetall is used in Mg based alloy to produce bullets, shell and lighter flint.
Some individual Ln oxides are used asjphosphorus in television screens and similar fluorescing surfaces.

Some More Questions From The d-And-f-Block Elements Chapter

In the series Sc (Z = 21) to Zn(Z = 30), the enthalpy of atomisation of zinc is the lowest i.e., 26, kJ mol. Why?

The E° (M²⁺/M) value for copper is positive (+ 0.34 V). What is possibility the reason for this?

How would you account for the irregular variation of ionisation enthalpies (first and second) in the first series of the transition elements?

Why is the highest oxidation state of a metal exhibited in its oxide or fluoride only?

Which is a stronger reducing agent Cr²⁺ or Fe²⁺ and why?

Explain why Cu⁺ ion is not stable in aqueous solutions?

Actinoid contraction is greater from element to element than lanthanoid contraction. Why?

On what ground can you say that scandium (Z = 21) is a transition element but zinc (Z = 30) is not?

The outer electronic configuration of copper is 3d¹⁰ 4s¹, yet it is considered transition element. Why?

Mock Test Series

Mock Test Series

NCERT Sample Papers

Entrance Exams Preparation