Zadanie 2b
(b) Outline two safety precautions that must be taken during the preparation of propanoic acid, besides wearing a lab coat and safety goggles.
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(b) Outline two safety precautions that must be taken during the preparation of propanoic acid, besides wearing a lab coat and safety goggles.
(c) After 30 minutes, the student stopped heating the mixture and titrated a sample of the solution remaining in the flask with NaOH to determine the experimental yield of propanoic acid. Explain why the titrated sample will give an incorrect value for the…
(d) The student used distillation to obtain pure propanoic acid from the reaction mixture. (i) State two impurities, apart from unreacted propan-1-ol, that were present in the propanoic acid before distillation. (ii) The approximate experimental yield of…
(e) The propanoic acid obtained by the distillation was an aqueous solution with a volume of 22.5 cm3. Three 5.00 cm3 samples of this solution were titrated with 0.200 mol dm−3 NaOH to determine the accurate…
(i) State the number of protons, electrons and neutrons in . (ii) State the full electron configuration for . (iii) The relative atomic mass, Ar, of Rb is 85.47. Determine the relative mass of the first isotope of Rb to four…
(i) Explain why Rb has a lower first ionization energy than strontium, Sr. (ii) Outline why Rb has a lower electronegativity than potassium, K. (iii) Explain why oxygen, O, has a lower first ionization energy than nitrogen, N.
(i) Write the equation for the reaction of Rb with water, H2O, including state symbols. (ii) Describe the type of bonding in Rb and in H2O, and explain how the valence electrons in each produce that type of bond.
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