Chapter 18.4, Problem 18.6CP

(a)

Interpretation Introduction

Interpretation:

The formula of each hydride given in the picture has to be written and the compounds are either ionic, covalent or interstitial should be identified.

Concept Introduction:

The compound containing hydrogen and just one other element is called as binary hydride.  Type of hydride formed depends upon the element present in the group.  Types of binary compounds are, ionic hydride, metallic hydride and covalent hydride.

Ionic hydride: Ionic hydrides are formed by alkali metals and heavier alkaline earth metals.  They contain cations and ${\text{H}}^{\text{-}}$ anions in face centered cubic crystal.

Covalent hydride: Covalent hydrides are formed by non-metals.  These compound contains hydrogen which is bonded to another element by covalent bond.  Most of the covalent hydrides have relatively weak intermolecular force of attraction, so they are gas or volatile liquid at normal temperature.

Metallic hydride: Metallic hydrides are formed by transition metals, lanthanides and actinide metals in which hydrogen will be present in variable amount.  Metallic hydride has general formula of ${\text{AH}}_{\text{x}}$.  They are often called as interstitial hydride because they consists of crystal lattice of metals with smaller hydrogen occupying holes or interstitial.

(b)

Interpretation Introduction

Interpretation:

At $\text{25°C}$, the hydrides that are more likely to be solid and more likely to be gas should be identified and explained.

Concept Introduction:

The compound containing hydrogen and just one other element is called as binary hydride.  Type of hydride formed depends upon the element present in the group.  Types of binary compounds are, ionic hydride, metallic hydride and covalent hydride.

Ionic hydride: Ionic hydrides are formed by alkali metals and heavier alkaline earth metals.  They contain cations and ${\text{H}}^{\text{-}}$ anions in face centered cubic crystal.

Covalent hydride: Covalent hydrides are formed by non-metals.  These compound contains hydrogen which is bonded to another element by covalent bond.  Most of the covalent hydrides have relatively weak intermolecular force of attraction, so they are gas or volatile liquid at normal temperature.

Metallic hydride: Metallic hydrides are formed by transition metals, lanthanides and actinide metals in which hydrogen will be present in variable amount.  Metallic hydride has general formula of ${\text{AH}}_{\text{x}}$.  They are often called as interstitial hydride because they consists of crystal lattice of metals with smaller hydrogen occupying holes or interstitial.

(c)

Interpretation Introduction

Interpretation:

At $\text{25°C}$, the one hydride that gives basic solution on reaction with water has to be identified.

Concept Introduction:

The compound containing hydrogen and just one other element is called as binary hydride.  Type of hydride formed depends upon the element present in the group.  Types of binary compounds are, ionic hydride, metallic hydride and covalent hydride.

Ionic hydride: Ionic hydrides are formed by alkali metals and heavier alkaline earth metals.  They contain cations and ${\text{H}}^{\text{-}}$ anions in face centered cubic crystal.

Covalent hydride: Covalent hydrides are formed by non-metals.  These compound contains hydrogen which is bonded to another element by covalent bond.  Most of the covalent hydrides have relatively weak intermolecular force of attraction, so they are gas or volatile liquid at normal temperature.

Metallic hydride: Metallic hydrides are formed by transition metals, lanthanides and actinide metals in which hydrogen will be present in variable amount.  Metallic hydride has general formula of ${\text{AH}}_{\text{x}}$.  They are often called as interstitial hydride because they consists of crystal lattice of metals with smaller hydrogen occupying holes or interstitial.