In experiment 5, we are learning about density and specific gravity in measurements. Density is measured by mass divided by volume in order to get the ratio of the mass of an object to its volume. Specific gravity, on the other hand, is the density of a substance divided by the density of water and will cancel out the units in order to get a unitless measurement. Mass and Volume can be measured in two different ways, first mass can be calculated by directly placing it on the triple beam scale directly, or by weighing the difference. Volume can be calculated by displacement in the graduated cylinder or by calculating its dimensions. In this experiment, the objectives were to calculate the density of a solid by measuring its mass and volume, …show more content…
Part A of the experiment, we were measuring the density of water. In this part, we measured by difference by measuring the mass of the empty graduated cylinder which was 46.35 grams and then added 25.0 milliliters of water to it. When subtracting by difference, our mass of the water was 25.85 grams. This was close to the measurements of the water added to the graduated cylinder. The density of the water was 1.0 grams/milliliters. The second part of measuring for volume, we measured the density of Isopropyl alcohol the same way we did for the water. We measured the mass of the empty graduated cylinder which was 46.35 grams and then added 25.0 milliliters of Isopropyl alcohol to it which made the mass 66.95 grams, causing the difference to be 20.6 grams of the Isopropyl. This was 4.4 grams less than what it should have measured out to be. The last part of experiment 5, was learning about specific gravity and temperature. Specific gravity does not have any units, it is unitless. When measuring for the temperature, we used a thermometer to calculate the Celsius of the water, 10% sodium chloride, and isopropyl alcohol. The specific gravity uses a hydrometer to measure the gravity of the liquids. Using the hydrometer, to figure out the measurements we have to look at it from top to bottom. The water for specific gravity was .998 while the temperature of it was 24
Furthermore, using a graduated cylinder with markings below the 100 mL line would have allowed for more accurate measurements of the initial volume of air in the graduated cylinder.
Measure the weight of a small stone to fit inside the opening of a 50ml graduated cylinder.
6. Determine the volume of water that has been displaced, by subtracting the initial volume of water from the final volume (VF) after adding 25 germinating peas. The difference in volume is
It was then placed in the ice bath, in which immediately the can slightly collapse on itself. In part two of the experiment, the prepared ice bath temperature measured at 1°C (T2). While the heated bath temperature stabilized around 85°C (T1) after 5 minutes, where it also began to simmer. The test tube with the rubber stop in the heated bath had no water for the entire 5 minutes. When the test tube was placed inside the ice bath for 5 minutes water appeared to flow inside the test tube. The amount of water that flowed into the test tube measured at 5 mL (Vw). When determining the volume of the test tube in the 100 mL graduated cylinder with 30 mL of water, it displaced the water up to 74 mL. Thus determining the volume of the test tube as 34 mL
In my experiment, I will use an overall volume of 50 cm³ of 2moles of
3. Add on of the following volumes of distilled water to the test tube, as assigned by your teacher: 10.0mL, 15.0mL, 20.0mL, 25.0mL, 30.0mL. (If you use a graduated cylinder, remember to read the volume from the bottom of the water meniscus. You can make more a more accurate volume measurement using either a pipette or a burette.)
I am going to carry out an experiment to measure the change in mass of
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.
Variables --------- During the experiments, the water will be heated using different spirit burners containing different alcohols. I will be able to change different parts of the experiment. These are the. Volume of water heated:
In a Styrofoam cup, record the temperature of the 200 ml of cold water. This is 200 g of water, as the density of water is 1 g/ml.
The Gravimetric Stoichiometry lab was a two-week lab in which we tested one of the fundamental laws of chemistry: the Law of Conservation of Mass. The law states that in chemical reactions, when you start with a set amount of reactant, the product should theoretically have the same mass. This can be hard sometimes because in certain reactions, gases are released and it’s hard to measure the mass of a gas. Some common gases released in chemical reactions include hydrogen, carbon dioxide, oxygen and water vapor. One of the best methods for determining mass in chemistry is gravimetric analysis (Lab Handout).
After each group member performed 20 trials for each type of glassware, we were able to use percent error and standard deviation to determine which types of glassware are accurate and precise. In this experiment, it was important to measure the temperature of the water in order to record accurate densities, which can impact the mass of the water.
...inty between 1.0% (0.1/10.00*100) and 2.13% in the measured volume and 0.1/4.70*100). We also used a digital thermometer that allowed us to read the temperature readings from five degrees celcius to eighty degrees celcius. Since the digital thermometer have an absolute accuracy of plus or minus one degree celcius, it gives a percent uncertainty between 0.125 % (0.1 / 5.00 * 100) and 0.2 % (0.1/ 80.0 * 100). One of the difficulties we faced during the lab is reading the inverted graduated cylinder. To account for the inverse meniscus, we subtracted 0.2 mL from all the volumetric measurements to account for that. Volumetric uncertainty is the most important in determining the accuracy of this experiment since we are constantly checking for the volume throughout the lab. It also is the factor that gives the highest percent uncertainty out of all the instruments used.
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.