Investigating the Volume of a Drop Essay

Criteria Planning (a) Planning (b) data Collection selective information Processing and Presentation proof and evaluationLaura HuLab Partner Tu Tai Kuong adeptted January 20, 07 perfect January 27, 07 5 pages + raw dataPlanning (a) and (b)Objective To accurately card the brashness of a omit of water and alter brininess water under two set temperatures.Hypothesis Since the mass of a substance changes as the temperature changes, we believe that the muckle of a liquified would change as temperature changes. This is because we know that niggardness is equal to mass divided by volume. Density is different dep finaleing on its temperature and mass is constant. Therefore, with a remnant in temperature, there go out be a difference in volume.The second thing we prognosticate is that season water will have a smaller volume per project than water. This is because the density of salinity water and the mass of sodium chloride water will be greater than normal water ascriba ble to the added flavor in the water. This will declare it heavier than regular water..Independent Variables Forces affecting the disembark as it is nigh to come shovel in ( gloom and chill of hand)Where to mold lands (may land on the sides of the beaker, making the slack stick to the sides instead of flingping to the bottom)Water evaporationAtmospheric pres surelyDropping device type (diameter of the place where the drop will comeout)Height from which the droplet will be dropped ( interrupt splashing)Saturation of common salt waterNumber of drops that will be testedLoss or increase in heat while conducting the experiment certified Variables Temperature of the liquidsThe type of liquidMaterials 2 Eye Droppers2 Thermometers2 Graduated cylinders (0.5ml increments)MicrowaveRefrigerator (set at 1 degree Celsius)Paper towelsSaturated salt water (table salt dissolved into water at roomtemperature until it can non dissolve anymore)Nestle Pure Life natural spring water (bottled wat er)4 Styrofoam cups1Procedures1.Prepare a data table with columns named Start volume, End gaudiness, Difference and ledger per drop.ExampleStart volumeEnd gaudinessDifferenceVolume per drop2. repose bottled water two Styrofoam cups. Take one of the cups and add table salt in it. Mix it until the salt will not dissolve any grander. Put both cups in the fridge. Set the fridge to 1 degree Celsius. Leave them there overnight.3. The next day, take out the salt water and mix it a step-up to make sure it is tinctured. Put the Styrofoam cup containing the salt water into a second Styrofoam cup.4. Take an nerve centre dropper, fill the eye dropper with salt water5. Take the gradatory cylinder and position it so that the end of the eyedropper is 2cm from the bottom of the graduated cylinder. Record the start volume of the liquid inside the cylinder (0 cm in this case).6. Slowly drop 10 drops into the cylinder, maintaining a 1 cm distance between the liquid and the end of the eyedroppe r. Record the volume. Dispose of the remaining water inside the dropper. Fill the dropper again with salt water. Drop 10 drops into the cylinder. Make sure to carefully count every drop Record the end volumes.7. Repeat step 5 five times.8. Clean out the graduated cylinder using solicit water, and use paper towels to dry it clean.9. Put the salt water back into the fridge.10. Take out the common un het water (from the fridge), put it in another Styrofoam cup and repeat what you did in step 5-8.11. Put the water in the microwave and heat it at high power for 1 minute.12. Take it out, stir the water, measure the temperature (and write it down) and use the water to do steps 5-8 again.13. Take the salt water out, microwave it at high power for 1 minute.14. Repeat what you did in step 12 for the salt water.15. Clean everything up.Data CollectionAttached to the back of the lab.2Data Processing and PresentationDifference = End volume start volumeEx. End volume = 2.11ml, start volume = 2. 00ml 2.11ml 2.00ml = 0.11 ml = differenceVolume per drop = Difference / 10 Ex. Difference = 0.11ml0.11ml/10 = 0.011ml = Volume per dropCold bottled water at 0.5+ 0.02 degrees CelsiusStar VolumeEnd VolumeDifferenceVolume per Drop2.00ml2.11ml0.11ml0.011 ml2.11 ml2.29 ml0.18 ml0.018 ml2.29 ml2.49 ml0.20 ml0.020 ml2.61 ml2.80 ml0.19 ml0.019 ml2.80 ml2.98 ml0.18 ml0.018 mlAverage volume per drop(0.011+0.018+0.020+0.018) / 5 = 0.0134mlRounded 0.013 mldubiety + 0.02 / 10 = + 0.002mlVolume per drop = 0.011ml to 0.015mlCold pure salt water at 0.5 + 0.02 degrees CelsiusStar VolumeEnd VolumeDifferenceVolume per Drop2.00 ml2.12 ml0.12 ml0.012 ml2.12 ml2.30 ml0.18 ml0.018 ml2.30 ml2.41 ml0.11 ml0.011 ml2.41 ml2.60 ml0.19 ml0.019 ml2.60 ml2.71 ml0.11 ml0.011 mlAverage volume per drop(0.012+0.018+0.011+0.019+0.011) / 5 = 0.0142 mlRounded 0.014 mlUncertainty + 0.02 / 10 = + 0.002mlVolume per drop = 0.012ml to 0.016mlWarm bottled water at 38 + 0.5 degrees CelsiusStar VolumeEnd VolumeDifferenceVolu me per Drop2.00 ml2.11 ml0.11 ml0.011 ml2.10 ml2.30 ml0.20 ml0.020 ml2.30 ml2.45 ml0.15 ml0.015 ml2.45 ml2.60 ml0.15 ml0.015 ml2.60 ml2.81 ml0.21 ml0.015 mlAverage volume per drop(0.011+0.020+0.015+0.015+0.015) / 5 = 0.0152 ml3Rounded 0.015mlUncertainty + 0.02 / 10 = + 0.002mlVolume per drop = 0.013ml to 0.017mlWarm saturated salt water at 38 + 0.5 degrees CelsiusStar VolumeEnd VolumeDifferenceVolume per Drop2.00 ml2.10 ml0.10 ml0.010 ml2.10 ml2.31 ml0.21 ml0.021 ml2.21 ml2.34 ml0.13 ml0.013 ml2.34 ml2.49 ml0.15 ml0.015 ml2.60 ml2.71 ml0.11 ml0.011 mlAverage volume per drop (0.010+0.021+0.013+0.015+0.011) / 5 = 0.014ml Uncertainty + 0.02 / 10 = + 0.002mlVolume per drop = 0.012ml to 0.016mlConclusion and EvaluationOur experiment tested two variables (the type of liquid and the temperature) and how they affected the volume of a drop. From our experiment, there is a slight difference between the volume of bottled water and the volume of salt water, so therefrom it proves that the volu me of a drop is dependant on the type of liquid we use.I also hypothesized that salt water would contain a smaller volume per drop than bottled water. This hypothesis was disproved in the experiment. We found that the volume of a drop of bottled water at 0.5 degrees Celsius is 0.01ml less than the volume of a drop of saturated salt water at 0.5 degrees Celsius.For our experiment, we couldnt prove that temperature affected the temperature affects the volume of a liquid because the volume of a drop of our bottled water increased by 0.02ml while the volume of a drop of warm saturated salt water remained exactly the selfsame(prenominal). Quite unexpectantly, we discovered that a drop of bottled water is greater in volume than a drop of salt water after theyre heated up to 38 degrees Celsius.All our data, however is only true IF we disregard the series of lab errors that may have neutered the results. Here is the list of lab errorsLab Errors1. Every drop that comes out of the eyedroppe r is a result of gravity pulling the drop of water out of the eyedropper opening. Because the force of gravity is constant, we can assume that every drop has the same volume, unless there was another force involved. This other force is the shaking of the hand holding the eyedropper. To prevent this, we first planned to tape the eyedropper to a ring stand. This way it would stay motionless so that no other force except gravity would act on every individual drop. Unfortunately, the eyedropper was not long enough to reach far enough into the graduated cylinder, therefore we held the eye dropped ourselves while dropping the liquids. For this reason, the shaking of our hand may have affected the results of our data.42. To prevent liquids from splashing onto the sides of the graduated cylinder, we decided to make every drop 1 cm above the liquid inside the cylinder. This would prevent each drop from making the water splash too much.3. Since we couldnt use the ring stand, the drops may hav e gotten stuck to the sides of the graduated cylinder because we couldnt guarantee that the eyedropper was held vertically over the water. Even if we did make sure it was vertically straight, our transfer might have shook, flinging the drop so that it would hit the side.4. Water evaporation may have occurred when we were performing the lab, so before recording the data for 10 drops, there may have been a piddling bit of water that had evaporated so each drop is actually slightly bigger than what we had recorded.5. We are not 100 percent sure that we counted the correct number of drops because there seems to be a few trials that had an signally large volume compared to the other trials. This may have also been because the water stuck to the sides of the graduated cylinder came down and added to the volume of one trial.6. Since the graduated cylinder we used only went up in 0.5ml increments, we had to estimate the 0.01ml values. Our data may be off by 0.01 or 0.02ml (thus a + 0.02m l error).7. Atmospheric pressure affects the results slightly. This is something we cannot control, however we did the stallion in a short period of time, so the atmospheric pressure should have been somewhat the same during that period of time.8. We couldnt make sure that NO heat would be lost or gained when we took the coldwater from out of the fridge or when we took it out of the microwave. We insulated the water with 2 Styrofoam cups, but even that couldnt make sure that no heat would be gained or lost. Also, water would lose or gain heat as we are dropping each drop, or when it is sitting in the graduated cylinder, delay to be measured and recorded. For this reason, each drop may be a little bigger or smaller in volume than our recorded values.9. We tried to control the saltiness of the salt water by making it saturated salt water. To do this, we put much more salt than is needed to saturate the water, into the container. We stirred until no more salt was dissolved, or so it seemed. We couldnt be absolutely sure that the water was saturated because maybe the salt was just dissolving more slowly, but it was still creation dissolved.10. When we were heating up the water inside salt water, we still had a little bit of salt left on the bottom.. This may have caused a problem because when we wanted saturated water, we wanted it saturated at 0.5 degrees. After we heat the salt water, it wouldnt be saturated anymore, so more salt would be able to be dissolved into the solution. This means that the salt water after getting heated was slightly saltier than before it was heated.