BY: ARIANA RANDOLPH & ZACH STEINBAUGH Do Various Temperatures Effect Osmotic Rate?

Hypothesis: If boiling water/ the highest increase in temperature is used the osmotic rate will increase. Procedure Controls 1% of salt in solution 100 ml of distilled water in solution Size of potato core (size 5 core, 4.4 grams) Variables Temperature -81 °c, 4 °c, 21 °c, & 98 °c 1. Measure 100 ml of distilled water in a granulated cylinder(repeat 4 times then pour into a plastic cup) 2. Measure 1gram of salt (repeat 4 times and add to each plastic cup filled with H2O) 3. Create a core using the 5 th size corer out of a potato. Weigh each potato and add or subtract potato mass until it weighs 4.4 grams 4. Add a potato core to each cup 5. Label each cup numbered Place a cup in the freezer, fridge, room, and in boiling water 7. Let cups set for 30 mins then weigh the potato mass 8. Record proceedure

Data Original Core Mass (g) After Core Mass (g) Percent Change in Mass (g) (after-original/after *100) Number 1: freezer 4.4 g Number 2: fridge 4.4 g Number 3: room temperature 4.4 g Number 4: boiling water 4.4 g

Before After Pictures

Descriptions Number 1: freezer Number 2: fridge Number 3: room temp. Number 4: Boiling water Felt cold/icy Hardened from temp Could tell that water had been absorbed Felt cold/but not icy Slightly harden Could tell that water had been absorbed Same hardness as before Could tell that water had been absorbed Lightened in color Softened It appeared that the most water had been absorbed

Conclusion The purpose of the experiment is to conclude if various temperatures effect the osmotic rate. Our data resulted in number 1(freezer) changing mass by 7.368%, number 2(fridge) changing mass by 6.38%, number 3(room temp) changing mass by 3.297%, and number 4(boiling changing by 6.977%. It was originally predicted that boiling water would increase the osmotic rate, therefore our hypothesis was rejected because our data shows that the highest increase in osmotic rate was caused by a freezing temperature. Experimental Errors The solutions (with core) were only left for 30 minutes. Better results would have occurred with more time. The core size was made equivalent with added core pieces if the core was not originally 4.4 g Human Errors Because the weight of the core was measured with a triple beam balance there is probable human error in measuring

Explanation We learned: That the results should have proved the hypothesis; the warmer the salt solution the higher the osmotic rate. Because our data disproved the hypothesis it has been concluded that time was a key variable. In order to correct the data, diffusion needs to take place for a duration of time starting at 1 hour up to an overnight experiment. Osmotic rate is directly related to diffusion of molecules and how diffusion starts with-in a single cell