An impure sample of Na2 SO4 has a mass of 1.56 g. This sample is dissolved and allowed to react with BaCl2 solution. The precipitate has a mass of 2.15 g Calculate the percentage purity of Na2 SO4 in the original sample.

Use this information to determine the number of calends electrons in the atoms. which of the following correctly compares the stability of the two atoms? a) both are unreactive b) both are highly reactive c) a is unreactive and d is reactive d) a is reactive and d is unreactive

Ammonium perchlorate nh4clo4 is the solid rocket fuel used by the u.s. space shuttle. it reacts with itself to produce nitrogen gas n2 , chlorine gas cl2 , oxygen gas o2 , water h2o , and a great deal of energy. what mass of nitrogen gas is produced by the reaction of 2.1g of ammonium perchlorate?

Which process describes vaporization that takes place below the surface of a liquid? condensation melting boiling evaporation