• Join over 1.2 million students every month
• Accelerate your learning by 29%
• Unlimited access from just £6.99 per month
Page
1. 1
1
2. 2
2
3. 3
3
4. 4
4
5. 5
5
6. 6
6

# internal assessment vitaminC

Extracts from this document...

Introduction

Introduction Refer to Biology Handbook page 159 Aim To uncover the effects of heat on the amount of vitamin C in foods Research question What are the relationship between the length of time lime juice is boiled and the concentration of vitamin C in the lime juice sample? Hypothesis The longer the lime juice is boiled, the lower the concentration of vitamin C in the lime juice sample will be. Variables Independent variable: duration of boiling: - 0 min (fresh lime juice ), 10 min, and 1 hour Dependent variables: Concentration of vitamin C in lime juice sample Fixed variables: 1. Type of juice - Lime juice will be used throughout the experiment 2. Volume of DCPIP used in each titration - only 1 cm3 of DCPIP will be used in each titration 3. The person who decide whether the colour change of DCPIP - The same person will decide whether the DCPIP had reduced to colourless solution or not. 4. Environment - the experiments will be conducted at the same place so that the temperature and pressure of surrounding will be constant. ...read more.

Middle

0.80 35.40 34.6 2nd 0.30 31.60 31.3 1 hour boiled lime juice 1st 0.50 35.70 35.2 2nd 0.20 34.00 33.8 * Solution is the mixture of glacial acid, respective lemon juice and distilled water. Table 1: volume of solution used in the titration Data Processing * The average volume of titrated juice = * The concentration of ascorbic acid in each juice can be calculated using the following formula; The mass of ascorbic acid equivalent to 1 cm3 of DCPIP = 0.05 mg1 In n cm3 of juice solution = 1 cm3 DCPIP Hence, the volume of lime juice sample titrated contains 0.05 mg of ascorbic acid Therefore, the concentration of ascorbic acid in sample = mg ascorbic acid = X Therefore, concentration of ascorbic acid in pure juice, = Concentration of ascorbic acid in pure juice = 25% X * Uncertainty = % uncertainty of average volume used in titration Juice Average volume used, � 0.10 cm3 Concentration of ascorbic acid, mg cm-3 Fresh lime juice 26.25 0.0476 � 0.4 % Boiled lime juice (10 min) ...read more.

Conclusion

2. Vitamin C, one form of ascorbic acid, can be denatured by high temperature breaking it into simpler molecules. The longer the lime juice is boiled, the higher the amount of vitamin C that will be denatured and thus decreasing the concentration of vitamin C in lime juice. 3. We can relate this result of experiment in our daily life such as cooking. In order for us to get the maximum benefit of eating fruits and vegetables, we should reduce the time of cooking of the fruit or in some cases, just eat them raw so that the amount of vitamins in them is the highest. 4. The function of acetic acid in this experiment is to minimize the acidic effect of ascorbic acid as it can lower the temperature of the solution. Conclusion From the result, the longer we boil the juice sample, the lesser is the content of ascorbic acid in the sample. So, we can conclude that the longer we cook our food, the lesser is the content of vitamin C in them. 1 International Data Standard, July 1980 ?? ?? ?? ?? Zubair Abdur Rahim bin Ahmad M08L Measuring the concentration of vitamin C ...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 Biology 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

# Related International Baccalaureate Biology essays

1. ## Osmosis Internal Assessment (Biology)

4 star(s)

All potatoes used are from the same bag, of similar size, skin colour and shape v. Materials and Apparatus Materials Quantity Uncertainty Distilled Water (H20) 300ml ?1ml Potatoes (Medium Sized) 4 - Apparatus Quantity Uncertainty Electronic Weighing Scale 1 ?0.1gram Stopwatch 5 ?0.1second Forcep 1 - Scalpel 1 - Ruler 1 ?1mm Cylindrical food borer (1cm diameter)

2. ## Vitamin C concentration

Ascorbic acid II. Rutinoscorbin and new lemon juice III. Orange juice from carton IV. Old lemon juice V. Orange juice VI. Tomato juice VII. Tomato juice from carton The results present that our everyday nutrition should include as much of the solutions above as to reach the daily need for the ascorbic acidiii.

1. ## Biology Internal Assessment Peas Lab

2 The reason we saw the sufficient increase in the temperature of the flask with boiled peas was not because they were respiring, but because the chemicals are broken down, which breaks their chemical bonds thus releasing energy (heat). By going through all of what I just stated, it seems

2. ## Biology- Extended essay. For this research, I investigated the effects of DDT and ...

water, in through the mouth, over the gills and out of the operculum. The method of pumping water over the gills seems to differ in detail according to the type of fish but, in general, the pressure in the mouth cavity is reduced by the floor of the mouth being lowered.

1. ## The Effect of Temperature on the Vitamin C Content of Lemon Juice

DCPIP is blue in its oxidised form¹, so with the addition of vitamin C (or in this case lemon juice which contains Vitamin C) the DCPIP is reduced, forming a colourless substance.

2. ## How does cooking affect the amount of vitamin C in lemon juice?

Data Processing The volume of lemon juice sample used in the titration can be calculated by using the formula: Volume of lemon juice sample used = final reading ? initial reading Uncertainty of volume of lemon juice used = uncertainty of final reading + uncertainty of initial reading Below

1. ## Effect of Incandescent, Fluorescent and LED lights at 900 lumens on the concentration of ...

- Concentration will be measured by finding the difference (initial- final volume) and plugging it in concentration equation C = n = v ________________ 3.97 ×10 −4 mols (V )

2. ## Biology Internal Assessment - investigate whether the Window and Notching caterpillar share the same ...

Alternative hypothesis: there is a significant statistical difference between distance from the midrib of the cabbage tree leaf to the nearest point of the notched and window feeding site. Calculating the degrees of freedom: (sample size) ? (the number of samples)

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