Question

identify the physical chemical changes from the following

i)burning of magnesium ribbon in air

ii)tarnishing of silver spoon

iii)sublimation of iodine

iv)electrolysis of water

Answer 1

1) Burning of magnesium ribbon in air is a chemical change as magnesium reacts with oxygen to form magnesium oxide.
2) Tarnishing of silver spoon is a chemical change as silver forms a layer of silver sulphide.
3) Sublimation of iodine is a physical change.
4) Electrolysis of water is a chemical change.