Observe any changes on the filter paper.
 20 Which element can easily form chains? When freshly cut, they rapidly tarnish by reaction with oxygen to form an oxide layer, which is why they are stored under oil.
This increases the mass of the cathode.
Don't forget that this is just a tiny part of a giant structure extending on all 3 dimensions.
 30 The total number of electrons in one molecule of carbon dioxide is a 22 b 44 c 66 d 88 Answer: A.
Calculate the composition of the alloy.