O level chemistry 2019 5070/42 Answers
5070/42 Answers Q1)Table: 23.6, 0.3 Tick on 23.6 and 23.8 Mean 23.7 Moles of HCl: 0.01398 Moles of Magnesium Hydroxide: 0.00699 Mass of Mg(OH)2: 0.405(42) Mass of Milk Of Magnesia : 11.7 % = 3.46~ Q2) Chromatography se karna tha Electro Chemistry: Cathode: pink deposits Anode : Colorless gas. Observation with inert: blue color fades away COLOR CHANGE WITH Cu electrodes: No change. Mass of Anode Decrease Mass of Cathode increase Graph Question: Color Change of Sol; Colorless to Brown Q) Why did addition of CaCO3 stopped rxn. A) Acid was nuetralized... Anomalous Point : 100,11.0 Volume: 13.0~15.0 (Depends on Graph) Time : 85~95 (Again Depends on Graph) The gradient at 50s was steeper than At 400s Reason : More molecules, more effective collision, high Rate of Reaction. PREPARATION OF SALTS: a) 1. Excess CuCO3 in Sulfuric acid. 2.Heat/Stir 3.Filter 4. CRYSTALLISATION 5. WASH AND DRY. b) 1. Silver Nitrate + Ammonium Chloride 2. Mix, Stir. 3. Filter 4. Wa