Chapter 20, Problem 20.38SP

(a)

Interpretation Introduction

Interpretation:

The explanation for the order of atomic radii in the order $Sc>Ti>V$ has to be given.

Concept introduction:

Atomic radius: Atomic radius is the distance between the atomic nucleus and outermost electron of an atom. From the atomic radius, the size of atoms can be visualized. But there is no specific distance from nucleus to electron due to electron cloud around the atom does not have well-defined boundary.

The atomic radius follows general trend in periodic table that it gets decreases as we move from left to right and increases from top to bottom of the table.

Effective nuclear charge: It is the charge experienced by the valence electrons from the nucleus. Effective nuclear charge increases across a period because increasing nuclear charge with no accompanying increase in shielding effect.

(b)

Interpretation Introduction

Interpretation:

The explanation for the increase in order of density $Ti<V<Cr$ has to be given.

Concept introduction:

Density and atomic radii:

The relationship between density and atomic radii of elements is given by,

$\text{Density}\text{α}\frac{\text{1}}{\text{atomic}\text{radii}}$