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Baking Soda + Vinegar - Determin

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					Date: ___________________                                         Name: ________________________
Lab Table/Group:                                                  Lab Partners:
CHEM     LAB: PRODUCTION OF SODIUM ACETATE

Purpose:
In this experiment, you will produce sodium acetate from sodium hydrogen carbonate and acetic acid.

Overview:
Just about everyone has done the reaction of baking soda with vinegar to produce carbon dioxide gas.
From a chemist’s point of view, this is a combination of two reactions: (1) a double displacement reaction
of acetic acid (HC2H3O2) with sodium hydrogen carbonate (NaHCO3) to produce sodium acetate
(NaC2H3O2) and carbonic acid (H2CO3) (EQ 1), and (2) the subsequent decomposition of the carbonic
acid into water and carbon dioxide (EQ 2). As a side note, the source of the fizz in carbonated soda is
from carbonic acid decomposing into carbon dioxide and water. The chemical reaction equations are as
follows:
                   NaHCO3(s) + HC2H3O2(aq) → NaC2H3O2(aq) + H2CO3(aq)                               (EQ 1.)

                                   H2CO3(aq) → H2O(l) + CO2(g)                                      (EQ. 2)

In this experiment you will (1) react sodium hydrogen carbonate with acetic acid to make sodium acetate
and carbonic acid, and then (2) heat the product to drive off, by evaporation, any excess (unreacted) acetic
acid), CO2 and water in order to isolate the sodium acetate.

Equipment:
evaporating dish                     clay triangle                       ring stand
ring clamp                           balance                             gas burner
crucible tongs

Procedure:
     Precisely measure out 1 to 2 grams of sodium hydrogen carbonate, to the nearest 1/100ths place, into
     an evaporating dish of known mass. (Table 1, rows 1 & 2)
      Add 1 M acetic acid (5% acidity vinegar) to the sodium hydrogen carbonate drop wise until there is
      no longer fizzing when it is added.
      Gently heat the evaporating dish over a Bunsen burner until the sodium acetate is completely dry.
      Cool the evaporating dish.
      Determine the mass of sodium acetate formed. (Table 1, row 3)
      Calculate the number of moles of sodium hydrogen carbonate used. (Table 1, row 4)
      Calculate the moles and mass of sodium acetate that should have been produced from this quantity
      of sodium hydrogen carbonate. (Table 1, rows 5 & 6, respectively)
      Calculate the percent yield & percent recovery for the sodium acetate (Table 1, row 7).
CHEM                                      LAB:   PRODUCTION OF SODIUM ACETATE       P.2




Table 1. Data & Results (Show all calculations!) & Grading Rubric
                                                                                POINTS

1.     Mass of evaporating dish:                                                    2
2.     Mass of sodium hydrogen carbonate (before addition of vinegar):              2
3.     Mass of sodium acetate formed (after heating):                               2
4.     Number of moles of sodium hydrogen carbonate used.




                                                                                    3
5.     Number of moles of sodium acetate that should have been produced.




                                                                                    3
6.     Mass of sodium acetate that should have been produced.




                                                                                    3
7. NNumber of moles of sodium acetate that were actually produced.
   u
   m




                                                                                    3
8.     Percent Yield and Percent Error:




                                                                                    2
CHEM                                    LAB:   PRODUCTION OF SODIUM ACETATE   P.3




9.     Name, date, lab group, partners, general neatness:                      1
10. Lab performance (e.g., safety, doing the lab, cleanup)                     4
11. TOTAL POINTS:                                                             25

				
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