Answer:
When the sun shines onto a solar panel, energy from the sunlight is absorbed by the PV cells in the panel. This energy creates electrical charges that move in response to an internal electrical field in the cell, causing electricity to flow.
Hydrogen (H) has a molar mass of about 1.007 g/mol and has 1 electron.
Oxygen (O) has a molar mass of about 15.999 g/mol and has 8 electrons.
Then water (H₂O) has a total molar mass of about 18.015 g/mol and has 10 electrons.
30 g of water is the mass of
(30 g) × (1/18.015 mol/g) ≈ 1.66528 mol
of water. Recall that 1 mole is around 6.022 × 10²³ molecules (i.e. Avogadro's number). So 30 g of water is the mass of approximately 1.00285 × 10²⁴ molecules of water.
If each molecule contains 10 electrons, then 30 g of water contains 1.00285 × 10²⁵ ≈ 10²⁵ electrons.