Introduction:
The purpose of this lab is to the concentration of acetic acid in vinegar that is missing. Its also to acknowledge that in some chemical reactions a drop can mess up the hole lab. Its is also to get some experience using the materials to do well on the lab in the FSE.

Materials and Apparatus:
Apron
Goggles
Pipette
Suction bulb
Retort stand
Burette
Burette clamp
3 Beakers (250 mL)
3 Erlenmeyer flask (250 mL)
Labels
Meniscus reader
Sheet of white paper
Funnel
Table vinegar
Sodium hydroxide solution
Distilled water
Dropper bottle containing phenolphthalein













Safety Precautions:
Both vinegar and sodium hydroxide are corrosive. Wash your hands immediately is any of those chemicals has spilled on your hands. Ask the teacher what do if any chemicals were spilled on the counter.
Procedure:
For each liquid a clean, and dry beaker was labelled. The pipette and the suction bulb were obtained, the pipette was rinsed in distilled water, then with vinegar. From the pipette 10 mL of vinegar were added to the Erlenmeyer flask. Then 20 mL were added, also 3 drops of phenolphthalein indictor. The burette was rinsed with distilled water, then with sodium hydroxide. The retort stand, burette clamp, burette, and the funnel were set up. Sodium hydroxide was pored in the pipette to fill it, and the funnel was removed before the titration was started.
A white tissue paper was placed under the Erlenmeyer flask, to make it easer to identify when the colour is changing. The left hand was always on the stop cock, to get full control, while the Erlenmeyer flask was being swirled all the time. The end-point would be within 2 or 3 drops. If 1 extra drop was entered then it will turn very dark pink. This whole process repeated two more time, then the results were recorded. After the was done, all the chemicals were pored in the dink with a lot of water with it. Then all the materials were cleaned and placed back in there appropriate spots.




Analysis:
Average volume = (8.01mL + 8.05mL)
2
Average volume = 8.03mL
Figure 1


NH3COOH(aq) + NaOH(aq) ® H2O(l) + NaCH3COO
Figure 2


NaOH = 8.03mL ® 0.0083L
NaOH = 1.00 M
NH3COOH = 30.0 mL ® 0.03L
0.0083L * 1.00 M = 0.0083 mol
0.0083mol * 0.03L = 0.276 M
Figure 3



NaOH = 8.03mL ® 0.0083L
NaOH = 1.00 M
0.0083L * 1.00 M = 0.0083 mol
0.0083 mol * 60.06g/mol (molar mass) = 0.498 g
Figure 4


Density(vinegar) = 1.01 g/mol
Volume(vinegar) = 30.0mL
1.01g/mL * 30.0mL = 30.3g
Percent by mass of acetic acid in vinegar:
= Mass of solute *100%
Mass of solution
= 0.498g *100%
30.3g
= 1.64%
Figure 5
The average if the 2 volumes are 8.3 as shown in Figure 1. The chemical formula for the reaction is shown in Figure 2. The concentration for acetic acid in vinegar is 0.276 M as shown in Figure 3. The mass of acid in the volume of vinegar is 0.498 g as shown in Figure 4. The mass by percent of acetic acid in the sample is 1.64%as shown in Figure 5.
Some sources of error were the burette that was chosen, its stop-cock was to hard to open or close, when made it difficult to do the lab. It was so hard to dry out the Erlenmeyer flasks from inside, because of their narrow opening.
Some people rinse there hair with vinegar after using the shampoo, to neutralize it, because the shampoo can me acidic to the point that will melt down the hair after a while.