• Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

Which fruit juice (Orange, Apple, Peach, Pineapple, and Apricot) has the highest concentration of ascorbic acid?

Extracts from this document...


Dafna Bicaci IB Chemistry SL Acids & Bases - Design Lab ASCORBID ACID CONTENT DESIGN LAB PURPOSE: Which fruit juice (Orange, Apple, Peach, Pineapple, and Apricot) has the highest concentration of ascorbic acid? VARIABLES: 1. Independent Variables: In this experiment, my independent variables are the different fruit juices; apple, apricot, peach, orange and pineapple. 2. Dependent Variables: The dependent variable in this experiment is the concentration of ascorbic acid the fruit juice contains which is calculated by the formula: , in this case, (Concentration(DCPIP) x Volume(DCPIP))/ Volume(Ascorbic Acid) = C(Ascorbic Acid) 3. Controlled Variables: 1. I will use the same brand of fruit juice for every trial 2. The juices will be diluted with 10 mL distilled water. 3. I will use 0.1 mol/dm3 of DCPIP for each trial. MATERIALS: 1. 30 mL each of ?Tamek? brand Apple Juice, Orange Juice, Pineapple Juice, Apricot Juice, and Peach Juice 2. Graduated cylinder 3. 100 milliliters of dichlorophenolindophenol (DCPIP) ...read more.


When acid and base react, the reactants are salt and water. The reaction in this experiment was 1:1. Therefore, to calculate the concentration of ascorbic acid in the juices, I use the formula below: . Calculated concentration of Ascorbic Acid (mol): Calculated Concentration of Ascorbic Acid (moldm3) APPLE 0.029±4.07% ORANGE 0.146±2.62% PEACH 0.027±3.54% PINEAPPLE 0.052±2.18% APRICOT 0.028±3.41% The table above shows the concentration of ascorbic acid of each fruit juice calculated from the volume of DCPIP, concentration of DCPIP and volume of ascorbic acid. It can be seen that they all have different concentrations of ascorbic acid however, they are very close to each other. An example of the procedure of calculating the concentration of ascorbic acid is below: APPLE JUICE TRIAL 1 TRIAL 2 TRIAL 3 Concentration of DCPIP 0.1 mol 0.1 mol 0.1 mol Volume of DCPIP 5.3 (±0.05) 4.2 (±0.05) 4.2 (±0.05) Volume of Ascorbic Acid 20 (±0.05) 20 (±0.05) 20(±0.05) Recorded values Apple Juice and DCPIP: Concentration of Ascorbic Acid = TRIAL 1ï Concentration of Ascorbic Acid = = 0.027 ±1.19% ...read more.


Evaluation: Limitations: This experiment was not done in a professional laboratory therefore there has been some limitations. First of all, the juices were kept in an open place therefore the concentration of ascorbic acid might have been oxidized in the air and therefore I might have recorded lower results as it should?ve been. Secondly, when fruit juice is dropped into test tube containing DCPIP solution, a suspension formed and its color slowly changes to black. The presence of the suspension in DCPIP solution makes it harder to determine whether DCPIP solution has been completely decolorizes. Another limitation would be that we considered there would only be ascorbic acid in the juices however, there might be other chemicals or different types of acid that has contributed to the neutralization process as well. Improvements: Since we did not work at a professional lab, there was no way to avoid oxidation of the ascorbic acid to the air. The only way to avoid that would working a little bit faster so there is less oxidation. In addition, using a colorimeter might help to determine completely colorization. This would help me by having results that are more accurate. ...read more.

The above preview is unformatted text

This student written piece of work is one of many that can be found in our International Baccalaureate Chemistry section.

Found what you're looking for?

  • Start learning 29% faster today
  • 150,000+ documents available
  • Just £6.99 a month

Not the one? Search for your essay title...
  • Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

See related essaysSee related essays

Related International Baccalaureate Chemistry essays

  1. Free essay

    Vitamin C in Fruit Juices

    In a 25-mL graduated cylinder, 20 mL of distilled water was obtained and added to the vitamin C solution in the flask. This helped with the ease in observing for the endpoint because the water added did not enter into either the reaction or the calculations.

  2. Testing antacids. The purpose of this investigation is to test different antacids mild ...

    Different amount of hydrochloric acid was slowly added with burette. Therefore, according to Appendix 1, Baking soda needed 28ml to neutralize one gram and tablet could not be measured. Alka-Seltzer needed 22.5ml to neutralize one gram and 72.045 ml to neutralize one tablet.

  1. Strong and Weak Acids And Bases

    0.01 HCl 2.00 Very Slow Little bubbles, foggy, H2 gas forming Experiment #5- Titration Theoretical Values HCl (aq) + NaOH (aq)--> H2O (l) + NaCl (aq) Molarities 0.2M 0.2M Volume 10ml ? It is a one-one ratio so: 0.20molHCl= 0.20mol NaOH= 10.0ml NaOH theoretically is needed CH3COOH (aq)

  2. Espuma a base de cscara de pia

    En esta monograf�a explicar� acerca de la espuma hecha con poliuretano. 4.1 OBTENCI�N DEL POLIURETANO El poliuretano es la poliadici�n del uretano. Este �ltimo se obtiene al hacer reaccionar un poliol con un isocianato. El isocianato es una sal de cianato, proveniente del �cido isoci�nico.

  1. IB Chemistry Lab Design - compare the effect of temperature on the concentrations of ...

    Then, the solutions of unknown concentrations are titrated and unitary method is used to calculate their concentrations. The concentration of Vitamin A is calculated using a redox titration. This is done by making a solution of acid dichromate, potassium iodide and starch.

  2. Chemistry Titration Acid Base Lab

    This is the reason why phenolphthalein was the best indicator. Graph A illustrates the different volumes of sodium hydroxide that was needed to reach the endpoint of the reaction when being added to a solution of vinegar using various indicators.

  1. The chemistry of atmospheric and water pollution.

    The following steps are undertaken by authorities such as Sydney Water to purify and sanitise water supplies for domestic use: Monitoring catchment area Authorities monitor the catchment area carefully to ensure that local soil run offs are avoided as this can increase the concentrations of unwanted ions.

  2. Measuring the fatty acid percentage of the reused sunflower oil after numerous times of ...

    Preparing the sunflower oil: In this investigation the experiment is based on sunflower oil which has had numerous potato frying. So it is also important to prepare fine samples for experiment. Firstly the oil which is going to be used in frying must be unused and the potatoes must be renewed for each frying.

  • Over 160,000 pieces
    of student written work
  • Annotated by
    experienced teachers
  • Ideas and feedback to
    improve your own work