Please help! Can you determine the atomic weights of zinc or copper by the metho
ID: 628187 • Letter: P
Question
Please help! Can you determine the atomic weights of zinc or copper by the methods used in this experiment? How? What additional information is necessary in order to do this? EXPERIMENT: CHEMICAL FORMULAS (a copy of the lab WITHOUT answers can be found in the following link: http://virtualinquiry.wikispaces.com/file/view/Chemical+Formulas+Lab.pdf). Zinc Chloride 1. Mass of evaporating dish and zinc : 54.140g 2. Mass of evaporating dish: 53.660g 3. Mass of Zinc : 0.48g 4. Mass of evaporating dish and Zinc Chloride : 54.633g 5. Mass of Zinc Chloride: 0.966g 6. Mass of Chlorine in Zinc Chloride : 0.486g 7. Empirical Formula : ZnCl2 8. Balanced Equation: ZN+2(HCl) --> ZnCl2+H2Explanation / Answer
let atomic weight of zinc be Z
mass of zinc = 0.48g
mass of chloride = 0.486 g
moles of chloride = 0.486 / 35.453 = 0.013708
therefore from empirical formula
moles of Zinc = 0.013708/2 = 6.854144 x 10^-3
mass of Zinc = 0.48g
therefore atmic mass of Zinc = 0.48/6.854144 x 10^-3 (moles = mass /atomic mass)
= 70.03306 amu