When electricity passes through water (H20), the water breaks down to form hydrogen gas (Hz) and oxygen gas (02).
Which equation represents this chemical reaction?
4 of 4 QUESTIONS
2H2 +02-2H20
2H2O → 2H2 + O2
2H20 + 02 → 2H2
2H20 + 2H2 - 02

Silver tarnishes as silver metal reacts with hydrogen sulfide, h2s, in the air. in this reaction, dark silver sulfide, au2s, covers the surface of silver. when silver is polished, this coating of silver sulfide can be removed from the surface. this makes the silver shiny again. enter the coefficients that balance the tarnishing reaction equation. (type 1 for no coefficient.)