Lab Report Diffusion is One of two kinds of passive transport, Diffusion can transport ions from higher concentration to lower concentration region without any other forces. – A net movement of molecules in and out of cell membrane Diffusion can be affected by the steepness of the concentration gradient. Lab question: Is the rate of diffusion influenced by the presence of second molecule? Prediction: the rate of diffusion is influenced by the presence of second molecule.
Material: Computer Vernier computer interface Logger Pro Vernier Conduactivity Probe three 18×150 mm test tubes with rack 1 5%, 10% salt water 400mL beaker dialysis tubing, 2. 5cm cm Dropper pipet or Beral pipet. Stirring rod Ring stand and utility clamp Lab Procedure: 1 . Connect the Conduactivity Probe to the computer interface, and run Logger. 2. Put beaker on the Ring stand and pour 400ml water into beaker. 3. get 1%, 5%, 10% salt water in to three dialysis tubes -Obtain 15 mL of 1%, 5% and 10% salt-water solutions in each tube. Soak three dialysis tubes into beaker one by one, and tie one end of the dialysis tubes. -Use a Beral pipet, transfer 15 mL of the 1%, 5% and 10% salt water into the dialysis tube – Tie off the other end of tube. ) 4. put a weak magnet into the bottom of beaker. 5. wait for 20 sec 6. record by logger pro for 120 sec for 3 times (1%, 5% and 10% salt water each) 7. ooserve ana compare all tne data 8. get conclusion 9. Put every thing back and trash all three-dialysis tube.
Questions: 1. The more salt concentration, the higher rate of diffusion will have. 2. my conclusion proved my prediction is right. Almost no difference. 3. to -4. 819 + 8. 886 Conclusions The diffusion rate of a molecule is influenced by the presence of a second molecule. I proved this by using different salt concentrations and showing the result on the computer by Logger Pro. Also, The rate of diffusion would be higher as the salt concentration getting higher.