Hypothesis: I predict that since pepsin interruptions down the stuff the quickest at a pH of 2 in the tummy. trial tubes # 3 will cut down the greatest because it has pepsin to further interrupt down the egg. Whereas the other trial tubings will hold a smaller decrease. I think test tube # 2 will hold the 2nd largest decrease rate and so # 6 because they all will hold a greater rate at interrupting down the stuff. Then. I predict the trial tubes that did non hold pepsin added will come in last in the order of trial tubings # 4. # 1.
and # 5.Manipulated variable:*Using different solutions to the trial tubing ( pepsin. distilled H2O. HCI. and NaOH )Controlled variable:*the same sum of solution poured into each trial tubing*ensuring that each trial tubing is cleanReacting variable:*The pH degrees and the size of the egg whiteMaterials:Hydronium pH paper6 big trial tubings ( 22*175mm )10 milliliter graduated cylinder10 % pepsin solutionKnifePincers or forcepsWax pen1. 0 mol NaOH solution1. 0 mol HCI solutionHard-bitten eggMetric swayerPlastic baseball mittsProcedure1 ) Using a wax pen label the trial tubes 1 to 62 ) Measure and cut 2cm regular hexahedrons of poached egg white.
Topographic point two regular hexahedrons in each of the trial tubing.3 ) Using the 10 milliliter graduated cylinder. step 5mL of distilled H2O and pour it into trial tubing # 2. Repeat the process. but step and pour 5 milliliter of HCI into trial tubing # 3 and # 4. Rinse the calibrated cylinder. Repeat once more. but this clip step and pour 5ml of NaOH into trial tubings # 5 and # 6.
A ) Why was the calibrated cylinder rinsed between adding HCI and NaOH solutions? The calibrated cylinder was rinsed between adding HCI and NaOH so that the two substances would non blend together to organize another chemical. which would non supply accurate consequences4 ) Topographic point a little piece of hydronium pH paper in each of the trial tubing.A ) Record the pH of each solution.5 ) Add 1 milliliter of pepsin solution to prove tubes # 2. # 4. and # 6. Topographic point stoppers on the trial tubing and position after 24 hoursdegree Celsius ) Using pincers or forceps. step each of the egg white regular hexahedronsvitamin D ) Compare the sum of digestion in the trial tubing.
Decision: The closer the pH degree was to 2. the greater it decreased in size. Test tubes # 3 and # 4.
with a pH of 2 reduced the greatest in size. whereas trial tubings # 6 and # 7 with a pH of 9 reduced the least. Test tubes # 1 and # 2 besides had a little decrease rate after twenty four hours.Beginnings of mistake: The pH paper might non hold been accurate because it was contaminated by people touching the paper.Laboratory application inquiries1.
Test tubing # 1. # 3. # 5 were all controlled trial tubing in the experiment2. Pepsin works best at a pH of 24. An alkalic metal in the tummy would finally decelerate down the digestion of saccharides. fats.
and proteins because an alkalic pH degree is greater than the pH of two. in which alkaline works best at.