Dear student
1) On adding a drop of Barium Chloride solution to an aqueous solution of sodium sulphate, white precipitate is obtained.This white precipitate is a barium sulphate.
BaCl2+ Na2SO4------>BaSO4 + 2NaCl
2) the other name of this reaction is double displacement reaction. Double displacement reactions may be defined as the chemical reactions in which one component each of both the reacting molecules is exchanged to form the products. Here barium chloride and sodium sulphate are reacting to form products.
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