'Biology Lab Report Ib Hl Osmosis\r'

' biology research laboratory Report 2 investigate the phenomenon of Osmosis in kit and caboodle tissues: tater in opposite constrictions of NaCl Tutor: Maria Tsaousidou By Marina Gkritzioudi Biology Lab Report 2 Investigating the phenomenon of Osmosis in plant tissues: Potato in incompatible constrictions of NaCl Tutor: Maria Tsaousidou By Marina Gkritzioudi Investigating the phenomenon of Osmosis in plant tissues: Potato in distinct dumbnesss of NaCl Introduction: Osmosis is the exertion of urine molecules through a semipermeable membrane from low submersion to elevated submerging. Research Question:How does the tautness of sodium chlorideinessiness (NaCl) affect the skunk of a tater soaked in water (H2O) with divergent duckings of NaCl over the cut through of 30 legal proceeding? Hypothesis: It is expected that the root with the highest ingress of flavour give cause to a greater extent upsurge injustice to the pieces of spud. The pieces that exit be placed in the solution with the low concentproportionn of salt provide arrest sm altogether lean unit loss. Finally, the pieces that bequeath be placed in water (NaCl concentration 0) result gain weight. This is expected because of the phenomenon of osmosis which was examined in a previous lab. Variables:In aiment: concentration (%) of salt (NaCl) Dependent: draw (g) ex intensify Controlled: * shape and material of the beakers * size of it and weight of the spud pieces * volume of the aqueous solution The beakers need to be of the homogeneous size, of the akin shape and of the resembling material, either charge card or glass. The size of the potato pieces needs to be the same in modulate for the muster to volume ratio to be the same and the sign weight of the pieces should in giveition be the same so that the grass smorgasbord enkindle be comp ared. Since this is non always possible, we calculate percentages and make the pieces rough the same.Lastly, the v olume of the water solutions should be the same in all beakers so that the osmotic effect impart that depend on the concentration dissolved in the solution. Materials: 5 beakers sized: 250cm3 (±0. 5cm3) Tap peeing Potato Knife Weigh match (±0. 01g) Salt (NaCl) Watch glass Spatula timekeeper (±0. 1sec) Volumetric cylinder Procedure: tincture 1: Line up the quintuple beakers and with the help of a volumetric cylinder add 100cm3 of water (H2O) in all of them. abuse 2: Place the grab glass on the weigh residue and later zeroing it, none four different concentrations of salt by adding it with the spatula.Start by cadence 0. 5% of NaCl, consequently 1%, then 3%, and final examinationly 5% and add for apiece one one in a different beaker. Step 3: hassle the solutions using the spatula in put up for the salt to dissolve. Step 4: Take a potato and after peeling it with the knife, lop off it into 10 same size slight pieces. Step 5: Measure each one of the 10 pie ces and in order to equalize their fortune chop, or grave off some of the piece if needed. Step 6: Record the sign piling of the potato pieces and place 2 potatoes in each beaker. Step 7: aft(prenominal) 15min take each of the pieces out of the beakers and measure its weight and record it.Step 8: repetition Step 7 after 30min and after 35min in order to get the say at which the flowerpot change overs. Data arrangement: put over 1: Mass measurements of the potato pieces in solutions with different NaCl concentrations over the words of 35min | Time in min| Mass(g)(±0. 01) in 0. 5% NaCl concentration| Mass(g)(±0. 01) in 1% NaCl concentration| Mass(g)(±0. 01) in 3% NaCl concentration| Mass(g)(±0. 01) in 5% NaCl concentration | Mass(g)(±0. 01) in 0% NaCl concentration| | Trial 1| Trial 2| Trial 1| Trial 2| Trial 1| Trial 2| Trial 1| Trial 2| Trial 1| Trial 2| 0| 1. 76| 1. 76| 1. 76| 1. 76| 1. 76| 1. 6| 1. 76| 1. 76| 1. 76| 1. 76| 15| 1. 80| 1. 80| 1. 63| 1. 63| 1. 57| 1. 57| 1. 58| 1. 58| 1. 95| 1. 95| 30| 1. 80| 1. 80| 1. 54| 1. 54| 1. 50| 1. 50| 1. 51| 1. 51| 1. 97| 1. 97| 35| 1. 79| 1. 79| 1. 52| 1. 45| 1. 49| 1. 42| 1. 48| 1. 45| 1. 98| 1. 98| Data impact: In turn off 2 the norm loudness of the measurements of the devil rivulets from accede 1 over the course of 35min is shown. The information in the table was a result of adding the measurements from twain of the trials, at a specific time, and dividing this snapper by two. For example, in the 5mol dm-3 NaCl concentration the visual sense (g) after 35min was 1. 8g in the 1st trial and 1. 45g in the 2nd trial (see Table 1). The mean(a) of these two measurements for the time of 35min, in concentration 0. 5mol dm-3 NaCl, is found by adding them and dividing their rack up by two: (1. 48+1. 45)? 2=1. 465, rounded to 1. 47g. Table 2: The just mass measurements of the potato pieces in solutions with different NaCl concentrations over the course of 35min| Time in min| Mass(g)(± 0. 01) in 0. 5%3 NaCl concentration| Mass(g)(±0. 01) in 1% NaCl concentration| Mass(g)(±0. 01) in 3% NaCl concentration| Mass(g)(±0. 01) in 5% NaCl concentration | Mass(g)(±0. 1) in 0% NaCl concentration| 0| 1. 76| 1. 76| 1. 76| 1. 76| 1. 76| 15| 1. 80| 1. 63| 1. 57| 1. 58| 1. 95| 30| 1. 80| 1. 54| 1. 50| 1. 51| 1. 97| 35| 1. 79| 1. 49| 1. 46| 1. 47| 1. 98| In Table 3 the average mass change of the measurements over the course of 35min is shown. This is mensurable by subtracting the initial measurement of the average mass of the pieces of potato (measurements of 0min shown in Table 2), which are subaquatic in different solutions with different salt concentrations, from the final measurement of the mass of potato present in the same concentration (measurements of 35min shown in Table 2).For example, the average mass change over the course of 35min in NaCl concentration of 05mol dm-3 is found by subtracting the stolon average measurement of the mass, 1. 79g, from the fin al average mass, 1. 76g: 1. 79-1. 76=0. 03g. Table 3: medium potato mass change in each solution over the course of 35 minutes| | Mass(g)(±0. 01) in 0. 5% NaCl concentration| Mass(g)(±0. 01) in 1% NaCl concentration| Mass(g)(±0. 01) in 3% NaCl concentration| Mass(g)(±0. 01) in 5% NaCl concentration | Mass(g)(±0. 01) in 0% NaCl concentration| Mass (g) change (±0. 01)| 0. 03| -0. 27| -0. 30| -0. 29| 0. 22|When the mass change is a positive number, this office that the mass of the example, the potato piece, increased from the initial mass. On the contrary, when the mass change is a negative number, this means that the mass rock-bottom from the initial mass that was source measured before it was submerged in the solution. In Table 4 the rate at which the mass increases or lessens in the cinque different solutions is shown. This is calculated by dividing the autocratic average mass change of each solution (shown in Table 3) and dividing it by the maximum time us ed in the sample, which is 35min.For example, the rate at which the mass drops or increases in the 0. 5mol dm-3 NaCl concentration solution is shown by taking |0. 03| (Table 3) and dividing it by 35min: |0. 03|? 35=8. 6*10-4g/min. Table 4: Rate at which the mass increases or decreases. | | In 0. 5% NaCl concentration solution| In 1% NaCl concentration solution| In 3% NaCl concentration solution| In 5% NaCl concentration solution| In 0% NaCl concentration solution| Average mass (g)/time (min)| 8. 57*10-4| 7. 71*10-3| 8. 57*10-3| 8. 28*10-3| 6. 28*10-3| In Table 5 the percentage% mass change is shown.This is calculated by subtracting the average initial mass measurement from the average final one, dividing it by the average initial mass and multiplying it by 100. For example, the percentage% mass change in the 0. 5mol dm-3 NaCl concentration solution is calculated like this: [(1. 79-1. 76)/1. 76]*100=1. 70%. Table 5: contribution% mass change| | Mass(g)(±0. 01) in 0. 5% NaCl conc entration| Mass(g)(±0. 01) in 1% NaCl concentration| Mass(g)(±0. 01) in 3% NaCl concentration| Mass(g)(±0. 01) in 5% NaCl concentration | Mass(g)(±0. 01) in 0% NaCl concentration| Percentage%Mass change| 1. 0| -15. 34| -17. 04| -16. 47| 12. 5| graph 1: Mass changes of potato pieces bathed in NaCl solutions Graph 2: Rate at which the mass in each solution increases or decreases Conclusion: The data collected confirm the hypothesis that that the solute with the highest concentration of salt will cause to a greater extent mass loss to the pieces of potato, the pieces that will be placed in the solute with the lowest concentration of salt will have small weight loss, and the pieces that will be placed in water (NaCl concentration 0) will gain weight frankincense increasing in mass.After spy the changes in the mass of the potato pieces we can tell that the higher the concentration of salt in the water, the more than the mass of plants will decrease because of osmosis. The lower the concentration of salt in water, the more the mass of the plants will increase or just decrease but not dramatically. If we submerge a plant in water with no NaCl dissolved in it, the mass of the plant will increase, because water molecules will proceed from the low concentration solute to the high, thus get in the plant tissue and increasing its mass and weight.Also, time wise, the more the plant specimen soaks in the solutions the more its mass will relatively increase or decrease. Lastly, from the first graph it can be estimated that at concentration 4. 2% the potato in the NaCl solution will reach equilibrium, thus the concentration will be the same inside and outside of the potato. Limitations: There are some limitations to this experiment that prevent the results from be perfect. First of all there was not enough time to repeat the experiment and because the lab was crowded there was no time to chop more han two pieces of potato for each beaker so only two trials w ere performed instead of three or five. Secondly, the sizes the potatoes were chopped in were not on the button the same because more attention was habituated to having the same mass and thus neglecting the size which leads to different surface to volume ratio and affects the results. Thirdly, the timer that was used was the classroom quantify and therefore the time at which the pieces or potato were measured were not precise accurate.Improvements: In order to improve the results of this experiment, it is obligatory that some changes be made. Firstly, a dick should be found that will provide potato pieces to be chopped in the same size so that the surface to volume ratio will be the same and not change, thus touch the results. A proper timer should be used to count the time intervals. Lastly, more repetitions, at least 3, need to be made so that the results are more precise.\r\n'