Question

Which of the following are liquid at a room temperature and how can you tell? I, Br, Ne, Pb, Hg.

Answer 1

You can't really tell unless you look at a periodic table. Iodine and lead are solids at room temperature, neon is a gas, and bromine and mercury are liquids. Usually there's a special way to color in the periodic table entry to indicate liquids. Solids tend to be towards the left side (metals) and gases tend to be halogens or noble gases, except for bromine and iodine.

Here you can see bromine and mercury are blue fonts.