In the salt and sand separation challenge our salt and sand measurements were off because we used to many transitions. We lost 6.79% of our sand and gained 10.97% of our salt. This shows that our procedure had flaws in it and should have been revised before we conducted the experiment.
We noticed changes in the weights of our equipment which caused our measurements to be incorrect. For instance, our filter paper went from a weight of 1.08 Grams to a weight of 1.11 Grams. This means that when we filtered our mixture, salt and/or sand was trapped in the filter paper which skewed our data by .03 grams. Also, the weight of our Dixie cup changed because as we were stirring the mixture we noticed flakes coming off the Dixie cup. Those flakes ended
The hypothesis that was formed in this experiment was that decantation and distillation were the techniques that would be successful in separating the three layered substances. The oil on top of the mixture was to be decanted solely, and the salt and sand layers would be distilled and separated together on filter paper on top of boiling hot water. The reason that the oil is decanted is because it doesn’t mingle with the salt and sand layers, and in addition it was the top layer, which was thought to have been easy to separate first. And as for the sand and salt, sand doesn’t mix and dissolve in water compared to salt, which does in fact dissolve, so distillation was thought to be the proper solution to separating the two
The mixture was poured through a weight filter paper and Sucrose washed with a 5ml of dichloromethane. The resulting solid was left in a breaker to dry for one week, to be measured. Left it in the drawer to dry out for a week and weighted it to find the sucrose amount recovered amount.
Random errors reflect a low precision through high scatter. Increasing the sample size of the number of tablets used will produce more data that can be graphed, and from which a more reliable and representative line of best fit could be produced, ultimately minimising random errors. Additionally, increasing the number of trials for each number of reacting Alka Seltzer tablets would minimise random errors by helping to produce a more precise average change in mass. Modifying the method can also help minimise the effect of random errors, by obtaining more reliable results. For example, instead of cutting the Alka Seltzer tablets in half, whole Alka Seltzer tablets could have been used, and the amount of reacting HCl could have been increased to account for the increase in the number of tablets used for each ample. In doing this, the mass of the reacting Alka Seltzer tablets will be more consistent for each trial, and the state of subdivision of the tablets could be truly kept
the replicate shows the same trend as the first experiment. I used a measuring cylinder and a beaker to measure out the amounts of water; however these did not seem to affect the quality of my results. To increase the accuracy of my results I could have perhaps used a burette. Even though I did the best I could to keep the experiment accurate, I did. some places there were mistakes that unintentionally occurred.
A random error is caused by any factor which randomly affects the amount of scatter in the data. An increase in sample size allows averages to be calculated which reduces the effects of these random errors. By removing outliers in the data, the effect of random errors can be further minimised. A large amount of scatter in results indicated low precision and a large number of random errors. Some possible random errors in this experiment may have arisen when measuring the 12mL of milk solution for each test tube; some may have had slightly more and others slightly less than 12mL. Another random error could have occurred when adding 4 drops of methylene blue, some drops may have contained more liquid than others, meaning some test tubes may have contained less methylene blue indicator than
In Regina Calcaterra’s memoir, Etched in Sand, the speaker is Regina as a ten-year-old female, who was being abused, and forced to grow up much faster than most, other children her age. She wrote this book to reach her siblings, and show her love for them; but she also was looking to reach out to children who were/are being abused, are in foster care, and who are homeless. The book was set in The Hamptons of Long Island, during the 1970s and 1980s. Regina and her four other sibling were being abused by their mother, who was hooked on drugs and alcohol, and was all around a very irresponsible person. This group of siblings, were moving quite often because their mother either did not remember to pay the bill, or they were sleeping in the back
In this experiment, there were several objectives. First, this lab was designed to determine the difference, if any, between the densities of Coke and Diet Coke. It was designed to evaluate the accuracy and precision of several lab equipment measurements. This lab was also designed to be an introduction to the LabQuest Data and the Logger Pro data analysis database. Random, systematic, and gross errors are errors made during experiments that can have significant effects to the results. Random errors do not really have a specific cause, but still causes a few of the measurements to either be a little high or a little low. Systematic errors occur when there are limitations or mistakes on lab equipment or lab procedures. These kinds of errors cause measurements to be either be always high or always low. The last kind of error is gross errors. Gross errors occur when machines or equipment fail completely. However, gross errors usually occur due to a personal mistake. For this experiment, the number of significant figures is very important and depends on the equipment being used. When using the volumetric pipette and burette, the measurements are rounded to the hundredth place while in a graduated cylinder, it is rounded to the tenth place.
Possible sources of error in this experiment include the inaccuracy of measurements, as correct measurements are vital for the experiment.
One possible source of experimental error could be not having a solid measurement of magnesium hydroxide nor citric acid. This is because we were told to measure out between 5.6g-5.8g for magnesium hydroxide and 14g-21g for citric acid. If accuracy measures how closely a measured value is to the accepted value and or true value, then accuracy may not have been an aspect that was achieved in this lab. Therefore, not having a solid precise measurement and accurate measurement was another source of experimental error.
I am going to carry out an experiment to measure the change in mass of
We’d note down the weight. Then we’d get our solutions ready. We were only given a 100% solution and a 0% solution, so we had to mix them in the right ratio to get all the solutions we needed. We decided to do 5 different types of solutions so we would have a wide range of results and it would be more accurate. We’d use 100%, 75%, 50%, 25%, 0% solutions in our experiment.
- Each teaspoon may not have been equal. Measurements were made based on judgment and not exact measurements.
First, the mass of the beaker being used was recorded, then about 1g of baking soda was added and the mass recorded. Next, the mass of just the baking soda was found and recorded. Then, the contents were boiled until dry then weighed and mass recorded after cooling off. Finally, the mass of jus the salt, or sodium chloride, was found and recorded.
Any chips caused by dropping or misuse of the instrument can cause a change in mass. Additionally, when dealing with some liquids there can be a chemical affinity between the liquid and the stem, depending on the material of which the hydrometer is composed. This can cause a buildup of material on the stem, altering the mass and thereby rendering the instrument out of calibration.
There is also the potential of human error within this experiment for example finding the meniscus is important to get an accurate amount using the graduated pipettes and burettes. There is a possibility that at one point in the experiment a chemical was measured inaccurately affecting the results. To resolve this, the experiment should have been repeated three times.