Magnesium bromide is an ionic compound whit the chemic formula mgbr2 what does the 2 tell you.

Name the element in group 17, period 2. (periodic table)

How do you know when a chemical reaction has occurred

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