Pure Chemicals Additive Lab Report

Purpose: To become familiar with the International System of Units and common laboratory equipment and techniques. To learn how to determine volume, mass, length, and temperature of a wide variety of items. To learn how to calculate density and concentration of dilutions.

There are several sources of error to this experiment due to random and systematic errors. The only source of random error was the measurement that we took through the graduated cylinder which was only accurate to the nearest 1%. We took the largest error from this one percent, which was +/- 3. The largest relative error this yielded was only 3%, so this did not affect how precise this experiment was too much. We can still make this more precise by making the masses of the water larger. For example if we started the masses at 300mL and went up by 50mL, the largest error this would yield would be 2% due to the largest error being +/- 5. This would cause smaller errors in the amount of water.

To start off the lab we did simple measurements with two different rulers, both measuring in centimeters but had different amounts of divisions on the second one making its measurements more precise. The first item to measure was a 13 x 100 mm test tube, again using the two different ruler’s metric ruler A and metric ruler B. After recording the measurements with the accurate rounding, we did the same steps to measure the diameter of a watch glass and an evaporating dish.

9. The accepted value for the density of water is 1 g/mL and the accepted density for isopropyl alcohol is 0.786 g/mL. Determine the percent error between your calculated densities and the accepted values for both water and isopropyl alcohol. Record the percent error in Data Table 4.

Our purpose in this lab was to create four solutions of the same components and different concentration. I found the concentration in Molarity (mol/liter). I would dilute a solution to create new solutions, using the formula M1xV1=M2xV2 where M=molarity and V=volume. In this lab, there were four solutions, Solution A, Solution B, Solution C, and Solution D. The solute or substance that dissolves was sugar and the solvent or substance that the solute dissolves in was water. For Solution A, I weighed 3.42 g sugar and diluted to 100 mL to get a concentration of 0.10 M and the color of bright red. For Solution B, I weighed 0.342 g sugar and diluted to 100 mL to get a concentration of 0.010 M and the color of pink. For Solution C, I measured 10

Other sources of errors maybe that the cube were placed too closely to surface of the beaker so its ability to absorb the solutions because the closest sides to each other could obstruct the process of osmosis by blocking their exposure to the solution or of the varying time at which the cubes were placed in the

This experiment was done in order to understand both fractional distillations and gas chromatography. In addition, this experiment was done to separate and identify two liquids that made up an unknown mixture. Gas chromatography was used to figure out the ratio of these two liquids.

Introduction: Accuracy and precision were the major aspects of the lab. Accuracy is how close the average of the measured values are to the actual value. Precision is the closeness of repeated measurements. In the lab, the aim was to get as close as possible with both accuracy and precision when determining the mass and volume of the spheres. The mass was determined by weighing the spheres on the Analytical Scale and Triple Beam Balance Scale. The volume is determined by measuring with a ruler and by water displacement. The standard

In the third stage of this experiment, the density of a liquid was determined and compared to known standards. A 100ml beaker was filled to about half-full with room-temperature distilled water. The temperature of the water in ◦C was recorded in order to compare to known standards later. A 50ml beaker was then weighed on a scale in order to determine mass and recorded. A sample of the distilled water with an exact volume of 10ml was then placed in the 50ml beaker using a volumetric pipette. The 50ml beaker with the 10ml of water was then weighed again and the initial mass of the beaker was subtracted from this mass to obtain the mass of the 10ml of water. With the volume and the mass of the water now known, density was calculated using d = m/V and recorded in g/ml. This process was then repeated to check for precision and compared to standard values to check for accuracy. Standard values were obtained from CRC Handbook, 88th Ed.

The density of regular Sprite was found to be 1.037 +/- g/mL. compared to Diet Sprite which was 0.9965 +/- g/mL. Among the three volumetric glassware Pipette was most precise (ó=0.0016 g/mL). Burette was the second best (ó=0.0023 g/mL) and graduated cylinder was the least precise (ó= 0.007 g/mL). Density was found to be intensive property. The slope of the graph of mass against volume was 1.05 g/mL, with the best linear fit for the data.

The purpose of this lab was to identify unknown substances using density. We had three unknown substances; a yellow liquid and two metal rods. For each substance we measured volume using the water displacement method in a graduated cylinder and mass using a triple beam balance. Then we calculated density using the formula density (g/cm3)= mass (g)/volume (cm3). The data we collected in the lab is in the table below. After comparing our data with the density chart we were able to determine the identities of the substances. The liquid was cooking oil and the rods 1 and 2 were copper and aluminium, respectively. In conclusion, density - a characteristic property- is important because even though many substances may look the same but have different

The volume of a small test tube and a thin-stemmed pipet were determined in this section of the lab. Water was poured into a small test tube until the water reached the very top edge of the test tube. The test tube was then emptied into a plastic 25 mL graduated cylinder and volume was measured and recorded into data table 3. A think-stemmed pipet was completely filled with water. Drops were carefully counted and emptied into the empty plastic 25 mL graduated cylinder until the water level reached 1 mL. The number of drops in 1 mL was recorded into data table 3. The thin-stemmed pipet had a total volume of 4 mL and that was also recorded into data table 3.

First, a 100 mL graduated cylinder was obtained and filled with 35 mL of water. A pipet was used to attain a more accurate amount of liquid. The water was then poured into a beaker, which was weighed on an analytical balance. Next, an Alka-Seltzer tablet was obtained and the weight measured using the same balance the weight of the beaker was measured on. When both masses were recorded, the tablet was dropped into the water. The liquid was swirled to allow for the tablet to dissolve completely. After the fizzing had stopped, the beaker was once again weighed and the mass was recorded. Each step was repeated seven more times for a total of eight trials. However, with each trial the liquids added to the beaker changed. In each new trial, an additional 5 mL of vinegar was added and 5 mL of water was taken away. Thus, beaker one had 0 mL of vinegar and 35 mL of water; beaker 2 had 5 mL of vinegar and 30 mL of water; beaker 3 had 10 mL of vinegar and 25 mL

Discussion: The volume of water can be measured in several different ways. This experiment uses pipets, burets, and a calculation to compare and analyze the accuracy of each measurement. When measuring water volume with a buret, first fill the clean buret with water and record the initial reading. Then mass an empty beaker and record this mass.

In order to obtain the true volume of volumetric glassware holds, this formula will be used.