How much positive and negative charge is present in 1 g of water? How many electrons are present in it?

Molecular mass of water is 18 gram, that means the number of molecules in 18 gram of water is 6.02 × 10²³

∴ Number of molecules in l gm of water = \(\frac{6.02\times10^{23}}{18}\)

One molecule of water (H₂O) contains two hydrogen atoms and one oxygen atom.

Thus, the number of electrons in ILO is sum of the number of electrons in H₂ and oxygen. There are 2 electrons in H₂ and 8 electrons in oxygen.

∴ Number of electrons in H₂O = 2 + 8 = 10

Total number of protons / electrons in one gram of water

= \(\frac{6.02\times10^{23}}{18}\) × 10 = 3.344 × 10²³

Total positive charge

= 3.344 × 10²³ × charge on a proton

= 3.344 × 10²³ × 1.6 × 10^-19 C

= 5.35 × 10⁴ C

This positive charge is balanced by equal amount of negative charge so that the water molecule is electrically neutral.

∴ Total negative charge = 5.35 × 10⁴ C