FOUNDATION PPSY 001chem chem best paper 100% correct

The manipulated variable of the experiment is the types of halides used. The responding variable is the reactions of halides in solution with certain reagents and the products formed in the reactions. When silver nitrate solution is added into potassium halide solutions, double displacement occurs. Silver halides, which are insoluble salts, are precipitated as they cannot dissolve in water. Besides that, KNO3 solution is also a product of the reaction. For the reaction between KCl (aq) and AgNO3(aq), a white cloudy solution and a white precipitate is formed. The white cloudy solution is the KNO3 solution while AgCl (s) is the white precipitate. The chemical equation is KCl (aq) + AgNO3 (aq) - KNO3 (aq) + AgCl (s). In dark condition, the colour of solution and precipitate remains the same. However, when it is put under light, AgCl is very sensitive to light and decompose into Ag and Cl, with an equation of: 2AgCl (s) +light - 2Ag(s) + Cl2 (g). This forms a grey solution with grey precipitate, which is Ag (s)