because of the shift in the reduction potentials during electron transfer reaction.

Many of the energy conversions that go on in a cell involve reactions in which an electron is transferred from one substance to another. This is because the transfer of an electron also involves the transfer of the energy of that electron. Such an electron transfer is called a redox reaction. Examples are photosynthesis and cellular respiration

It is a bond that transfer electron.

This is known as electron-transfer (ET).

show the electron transfer in the ionic compounds using Lewis dot symbols

MgBr2

Na3N

LiF