Testing the reaction rate of fermentation based on alterations in ph solutions. Emily Anderson Abstract The experiment was conducted to determine what effect different ph solutions would have on the reaction rate of yeast fermentation. It was hypothesized that, the more acidic a ph solution, the slower the reaction rate would be in fermentation process. The reaction rate was judged by the amount of co2 displacent formed in the top of the fermentation tubes every five minutes for twenty minutes intervols. Introduction When the oxygen supply runs short in heavy or prolonged exercise, muscles obtain most of their energy from anaerobic process called glycolysis.
Once calculated, these results can be analyzed and will either validate or refute my hypothesis. Introduction (Library Research): Ascorbic acid (vitamin C) is found in orange juice. In this experiment, orange juice made from the concentrate was measured for decreases/increases of off-flavours (furfural and α-terpineol) and for decreases/increases of ascorbic acid. Sodium hydroxide (NaOH) as well as hydrochloric acid (HCl) were added during separate trials to change the PH in the orange juice. An increase of PH from 3.2 to 4.2 enabled the protection of ascorbic acid levels, without increasing the levels of other enzymes.
* Secondly you have to add five drops of phenolphthalein the test tube which you are using. * Then measure out 5 cm of milk using a syringe or a measuring cylinder, and then add this to the test tube. * After this measure out 7 cm of sodium carbonate solution using a different measuring cylinder or a syringe and then add this to the test tube, which will make the solution turn pink. * Next you will have to place a thermometer in the test tube, but you will have to be careful as the experiment could fall over. * Then you will have to put the test tube in a water bath and leave it until the contents reach the same temperature as the water bath.
956). To isolate caffeine from various substances requires different methods based on the composition of the solution it is being extracted from. High pressure processing is a new method that extracts caffeine from tea leaves and has been shown to have an advantage such as shorter extraction times (Nature.com). Similarly, the process of extracting and sublimating this ingredient from tea leaves was performed in the following experiment and its concentration was determined. Methods When the prepared tea solution has cooled down to room temperature, transfer 10-mL of tea into two centrifuge
Place the tube in the other test tube so that the tip is fully submerged in water 8. Reset the stop watch and count how many bubbles come out of the tube and stop counting after a minute has passed by. 9. Record data 10. Repeat steps 8 and 9 two more times Repeat steps 4, 5, 6, 7, 8, 9 and 10 for these other values 4%Glucose/10% Yeast 86% Water 6%Glucose/10% Yeast 84% Water 8%Glucose/10% Yeast 82% Water 10%Glucose/10% Yeast 80% Water 11.
Hypothesis My hypothesis is that the volume of carbon dioxide released from the yeast will be high when it is respiring with glucose and fructose, but with lactose, as it is a disaccharide and the yeast does not contain the enzyme lactase, which is needed to break lactose down. Method 1. For each repeat, the 3 boiling tubes were set up in a test tube rack, each containing 4cm3 of 30% yeast solution and 4cm3 of the 15% sugars: glucose, fructose and lactose. 2. 5 drops of Janus Green solution was then added to the substrate, in order to indicate when the substrate would begin anaerobic respiration.
IB Internal Assessment Objective: Investigate the Effect of Temperature on the rate of Digestion of Gelatine by Trypsin OBJECTIVE OF THE INTERNAL ASSESSMENT Research Question How will temperature affect the rate of digestion of gelatine by a 2% trypsin solution? Variables * The Dependent Variable is the time taken (seconds) for gelatine to digest. * The Independent Variable is the temperature (°C) we use to heat up the water bath for the solution. * The Controlled Variables are the size of the silver-acetate film pieces (1.5 x 1.0 cm), the volume of the 2% trypsin solution (3cm³), and the thermometers used to measure the temperature of the water in the tinc cans as well as the temperature of the 2% trypsin solution in the test tubes (the same thermometer was used at all times). RAW DATA AND OBSERVATIONS Initial observations 1.
Tannins, which are organic compounds that can bind to alkaloids such as caffeine, are going to be taken out of the tea water using sodium carbonate. The sodium carbonate is a base, which will convert the acidic tannins into sodium salts that are highly soluble in water. Isolating the caffeine will continue once methylene chloride is added to the remaining tea solution, which increases the solubility of the caffeine. Methylene chloride can be evaporated quickly leaving the caffeine to be purified by sublimation. Materials and Methods: The tea solution was obtained when a tea bag was placed in boiling water and its liquid mix was carefully squeezed into a beaker; and eventually placed into a test tube.
The problem of the experiment was as follows: How does the concentration of sugar in a solution affect the rate of the alcoholic fermentation being performed by the yeast cells? The independent variable of the experiment was the concentration of sugar in the apple cider. The dependent variable of the experiment was the time, in minutes; it took for the balloon to fill up with the carbon dioxide given off from the fermentation process. Finally, the hypothesis developed for the experiment was as follows: The higher the sugar concentration in the cider mixture, the less time it will take for the balloon to rise The procedure of the Alcoholic fermentation lab was as follows: 1. 3 test tubes, 3 balloons, a thermometer, a timer, a test tube rack, tape , and a marker will be needed 2.
Prediction: The potato chips will decrease in mass. Reasoning: Since the potato chips have a lower concentration of sugar, the water molecules from the potato chips will diffuse into the solution until they are both at the same concentration. Summary of Hypothesis The potato chips will increase in mass in solutions of lower sugar concentrations but will decrease in mass in solutions of higher sugar concentration. The Experiment -------------- I am going to carry out an experiment to measure the change in mass of potato chips left in a sugar solution for a period of 1 hour. I will carry out this experiment several times to ensure accurate results.