Question

When H+ forms a bond with H2O to form he hulydronium ion H3O+, this bond is called a coordinate covalent bond because ?

Answer 1

Both the shared electrons come from single atom

Step-by-step explanation:

Coordinate covalent bond is a type of bond in which both the shared pair of electrons are come from single bond. Whereas in simple covalent bond, sharing electrons come from both the participant atoms.

Coordinate covalent bond is also called dative bond and the atom which share both the electrons are called donar atom.

For a coordinate covalent atom to from, one participant atom should have lone pair of electron and other atom should be deprived of electrons.

In
`H_2O` molecule, O atom has lone pair of electrons while H+ ions has deficiency of electrons, so O atom shares its lone pair of electrons with H+ ions which results in the formation of coordinate covalent bond and forms
`H_3O^+ molecules`.

Answer 2

Because both the bonding electrons come from the oxygen atom.

Step-by-step explanation:

A coordinate covalent bond is formed when both the bonding electrons are coming from the same atom.

Here in the given situation, when H+ forms a bond with the water molecule
`H _ 2 O` to form the hydronium ion
`H _ 3 O +`, then it is referred to as a coordinate covalent bond since both the bonding electrons are coming from the oxygen atom.