What is made of 1 or more element chemically bonded through electron sharing?

The modern periodic table has groups.

At 450 mm hg a gas has a volume of 760 l, what is its volume at standard pressure

11. phosphorus-32 is radioactive and has a half life of 14 days. how much of a 124 mg sample of phosphorus-32 is present after 56 days? a) 7.75 mg b) 15.5 mg c) 31.0 mg d) 62.0 mg