hydrides

definition

the binary compounds of hydrogen with other elements are called hydrides.

ionic hydrides

they have ionic bonds in them. these are the hydrides of alkali and alkaline earth metals(1a and 2a group) except be and mg

properties of ionic hydrides

1. white crystalline solids

2. high melting and boiling points

3. conduct electricity in molten state

covalent hydrides

the hydrides which have covalent bonds in them are called covalent hydrides

properties of covalent hydrides

exist as gases or volatile liquids

low melting and boiling points

dissolve in organic solvents

non conductors

their bond energy depends on size and electronegativity

intermediate or polymeric hydrides

hydrides of be and mg represent the class of intermediate or polymeric hydries. their properties are in between ionic and covalent hydrides. they have polymeric structure and covalent nature.

trend in the periodic table

in a period, the covalent character increases

down the group, ionic character increases