If an element has 2+ valence electrons, does it transfer only one or more than one valence electrons

element having 2+ valence electrons can transfer its more than one electron that is 2 electron completely.

Explanation:

Group IIA have 2+ valency and two electrons in its valance shell.Its Electropositivity is  high and have the tendency to donate it two electrons.Element  of IIA form ionic with most electronegative element.

Examples:

Cu²⁺, Mg²⁺, Sr²⁺ are examples having  2+ valance electron

one of the following is examples of element that have 2+ valence electrons

MgCl₂

Atomic number of Magnesium (Mg) is 12

Electronic Configuration of Mg:

1s², 2s², 2p⁶, 3s²

or

K =2

L = 8

M = 2

So, it have to give its 2 electrons to form a stable compound.

Similarly

Chlorine atomic number is 17

Electronic Configuration of Chlorine:

1s², 2s², 2p⁶, 3s², 3p⁵

or

K =2

L = 8

M = 7

So, it have to gain one electrons to form a stable compound and complete its octet.

So,

Two chlorine atom as a molecule gain 2 electrons from Mg²⁺ atom

So one Mg²⁺ and 2 Cl⁻ atoms form an ionic bond

where in this ionic bond Mg²⁺ transfer its 2 valence electron completely and chlorine molecule accept 2 electrons.

                 ClMgCl

So the Answer is

element having 2+ valence electrons can transfer its more than one electron that is 2 electron completely.

Rethink and reinvent

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