Vitamin C Lab

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Equation

HX + NaOH NaX + H2O
1 mole1 mole1 mole1 mole

Aim
To analyze the Vitamin C from a rival company and compare with that of my company and find out the best value for the money spent by the consumer.

Controlled Variable
* Mass of the tablet and hereby vitamin C in rival company tablets * Consistency of components in the Vitamin C tablet
* Concentration of NaOH

Apparatus
1. Burette (50ml)
2. Conical flask (50ml)
3. Vitamin C tablet (1 tablet per one trial)
4. Sodium Hydroxide (NaOH) (500cm3)
a. The NaOH concentration in this experiment: 0.250 mol dm3 5. Digital Weighing Scale
6. Distilled water (500cm3)
7. Pestle
8. Mortar
9. Funnel
10. Phenolphthalein Indicator (50cm3)

Method for Cleaning Apparatus for Titration

* Check and confirm that the tap in the burette can be rotated smoothly. If not dismantle the knob and apply grease on the contact surface to reduce friction. Make sure the hole used for the liquid to flow is not covered by grease; this may cause a disturbance in the flow of fluid. Fix the tap back onto the burette. * Pour approximately 5 cm3 of distilled water and rinse the burette following this, pour approximately 5 cm3 NaOH and rinse the burette and make sure no distilled water molecules are stuck on the inner surface of the burette. * Turn the tap on and let the NaOH flow freely in the burette.

Diagram
Table 1 - Raw Data Table

Test No| Mass of Vitamin C ±0.01 (g)| Volume of NaOH Consumed (cm3)| Qualitative Data| | | Initial Volume
(±0.05)| Final Volume
(±0.05)| Difference
(±0.1)| |
1| 0.40| 0.00| 4.00| 4.0| Drop by drop, slowly done. Color was not instantly changed but slowly changed. Confident of result.| 2 *| 0.38| 11.20| 41.00| 29.8| Adding the indicator was forgotten. Not trustable result. Not a reliable data for analysis.| 3| 0.40| 40.00| 44.10| 4.1| Carefully done, confident of data. Slow drops, instant change in color - Reliable data| 4| 0.40| 45.20| 49.10| 3.9| Good trustable data. Drop by drop results, was achieved by half a drop of NaOH.| 5| 0.40| 0.00| 4.10| 4.1| Done carefully trustable data. Drop by drop results, instant change in color.|

*Test two is omitted because of highly inaccurate results for the reasons specified in the qualitative data Table 2 – Result Table

Test No.| Volume of NaOH Used (cm3)
(±0.04)| Concentration of NaOH
(mol dm-3)| No. of moles of NaOH
± 0.00004| Molar mass of C6H6O6H2 (g mol-1)| Mas of Vit. C in 1 tablet (g) ± 0.00004| Mas of Vit. C in 80 tablets (g)
± 0.00004|
1| 4.00| 0.250| 0.00100| 176.14| 0.17614| 14.09120|
2|  |  | Unreliable data, therefore no analysis was done|  |  |  | 3| 4.1| 0.250| 0.00103| 176.14| 0.18054| 14.44348|
4| 3.9| 0.250| 0.00098| 176.14| 0.17174| 13.73892|
5| 4.1| 0.250| 0.00103| 176.14| 0.18054| 14.44348|
| | | | | | |
| | | Average Mass (g) =| 0.17724| |

Table 3 – Price Comparison Table

Source of Vitamin C Tablets| Mass of each tablet (mg)| Vitamin C in Each Tablet (mg)| Filler material in each tablet (mg)| No. of tablets in each pack| Price per pack (Yen)| Price of each tablet (Yen)| Price per mg of Vitamin C bought (Yen mg-1)| Vitamin C consumption basis (1)| Vitamin C consumed per table (mg)| Price per mg of Vitamin C consumed

(Yen mg-1)|
My Company| 770| 500| 270| 100| 700| 7.0| 0.014| 60%| 300| 0.023| Rival Company| 400| 177| 223| 80| 600| 7.5| 0.042| 80%| 142| 0.053|

Table 4 – Value for Money Table

Source of Vitamin C Tablets| Price per mg of Vitamin C Purchased (Yen mg-1)| Price per mg of Vitamin C consumed
(Yen mg-1)| Value for money - Purchase Basis| Value for money - cosumption Basis| My Company| 0.014| 0.023| 300%| 230%|
Rival Company| 0.042| 0.053|  |  |

Calculation to find the mass of the content of Vitamin C...
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