-(iv), -(i), -(ii), -(iii)

List - I (Hydrides) List - II (Nature)

MgH 2 Ionic

GeH 4 Electron precise

B 2 H 6 Electron deficient

HF Electron rich

• Ionic hydrides are compounds formed between hydrogen and the most active metals, especially with the alkali and alkaline-earth metals.

• Covalent hydrides are formed when hydrogen reacts group 13 to group 17 elements.

• All the group 13 elements form electron deficient compounds with hydrogen.

• All group 14 elements form electron precise compounds.

• Elements from groups 15 through 17 form bonds which have excess electrons present as lone pairs.

Therefore,

• MghU is an ionic compound.

• GehU has sufficient number of electrons required for forming covalent bonds, hence it is electron precise compound.

• B 2 H 6 is electron deficient compound due to incomplete octet.

• HF is electron rich compound due to pair of unpaired electrons on fluorine.

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