Question

Which solution will form a precipitate when mixed with a solution of aqueous Na2CO3?

Answer 1

According to solubility rules, all compounds of alkali metals are soluble in water. Hence, all compounds of Na and K are soluble in water.

When Na₂CO₃ reacts with KNO₃, it gives NaNO₃ and K₂CO₃ which are soluble in water (Na and K salts).

According to solubility rules, all ammonium salts are soluble. when sodium carbonate reacts with ammonium chloride, it forms ammonium carbonate which is soluble(it decomposes to ammonia, water and carbondioxide, in the aqueous solution).

When treated with CuCl₂, CaCl2, BaCl2, it forms CuCO₃ CaCO₃ BaCO₃which is insoluble in water and precipitates out as a solid_.According to solubility rules, all carbonates, except that of ammonium and alkali metals, are insoluble.