Question

What are the very strong bonds that you have to break using electrolysis.

Answer 1

ionic bonds or the covalent bonds, also known as the intramolecular forces are very strong that they have to undergo electrolysis to break. i.e. \(\text H _2 \text O\)

Answer 2

Electrolysis actually tends to be mostly used to reduce the most active metals, on the left side of the Table. Things like calcium, sodium, titanium, aluminum.These occur naturally as oxides and carbonates, ionic compounds in which the metal atom is oxidized. It is very hard to get the electrons back onto the metal atom, i.e. to reduce it, so that you get the pure metal. Electrolysis is often the only practical way to prepare these metals from ores.