It is known that every mole of any substance contains Avogadro numbers of atoms/ions/electrons/molecules. This Avogadro quantity is equal to 6.022×1023.
Mass of 1 mole of water is 18 g as H2O has one atom of oxygen and two atoms of hydrogen and you can calculate the mass.hence 18 g of H2O has Avogadro number of electrons.Which is defined as the definition of 1 mole.hence 1 g of water contains 6.022×10^23/18 number of electrons and from this you can say that 100 g of water contains 100x(6.022×10^23/18)number of electrons and total charge is equal to one electronic charge multiplied by above number of electrons that comes out to be present in 100 g of water that is
1.6×10^-19x(100x(6.022×10^23/18)) coulombs.
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