You see electron configurations and the periodic table to answer the question which element is this fluorine carbon nitrogen or oxygen

Agas can holds 2.0 gal of gasoline. what is this quantity in cubic centimeters?

Find the mass, in grams, of 5.00*10^23 molecules of f2

Asample of hydrated tin (ii) chloride (sncl2) has a mass of 4.90 g. when it is dehydrated, it has a mass of 4.10 g. which is the correct chemical formula for the hydrate? sncl2•2h2o          sncl2•4h2o          sncl2•6h2o