Chapter 5, Problem 101QRT

(a)

Interpretation Introduction

Interpretation:

The element X has to be identified as metal or non-metal.

Concept Introduction:

Metal is defined as chemical element with certain physical and chemical properties.  Metals are effective conductor of electricity and heat, shiny, ductile, malleable, lustrous, elastic and easily forms bonds and cations.  Non-metals are materials which does not have properties of metal.

(b)

Interpretation Introduction

Interpretation:

The element with larger atomic radiushas to be given.

Concept Introduction:

Atomic radius: It is the distance between center of nucleus and outermost electron shell.  When two atoms are bonded together in a molecule, the sum of their radii should equal the distance between their centers.

(c)

Interpretation Introduction

Interpretation:

An element with greater ionization energy has to be given.

Concept Introduction:

Ionization energy:

In a gaseous state isolated neutral atom, the amount of energy required to eject an electron from outermost shell is known as ionization energy.  Ionization energy increases from left to right across periods due to increase of effective nuclear charge.  Ionization energy decreases down the group due to addition of electrons enters into new orbital which is far from nucleus.