Laboratory Techniques and Measurements Essay

Procedure: Using distilled water, premeasured containers and objects determine displacement of fluids and density of objects. Use ice and heat measure temperatures in Celsius, Fahrenheit and Kelvin.

In this lab the density of a glass marble was measured. Since the formula for density is mass divided by volume, the the mass of the glass marble alone was measured using an electronic balance. Afterwards, the volume of the marble was measured using the displacement water method. 20 mL of water was added to a 25 mL graduated cylinder and the amount added with correct precision and uncertainty was recorded. Once that step was complete, the graduated cylinder with 20 mL of water was slightly tilted so that the glass marble could be placed inside. The new volume was then recorded with correct precision and uncertainty. Then, the original volume was subtracted from the final volume to calculate the volume of the glass marble with the correct amount

The mass of the 100-ml. Graduated cylinder was measured without water but with the rubber stopper.

5. Calculate the mass of the water by subtracting “Mass A” from “Mass B.” Record the mass of the water in Data Table 4.

Since a graduated cylinder is usually used for liquid measurement, students think they need to put water in the cylinder. This is not

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.

A 100 mL graduated cylinder should be used to measure out ~40 mL of water.

6. Allow the crucible to cool to room temperature. Then weigh and record the mass of the crucible, lid, plus the residue that remains. Note that the weight of your sample is expected to decrease by at least 30 % of its original mass (~ 0.3 g).

Density of a Known and Unknown Rock By: Abigail Craig Experiment Partners: Andria Vallero, Erin McDaniel, and Ragib Murtic October 16, 2015 CHM 23000-23   Introduction Matter is described as any object that holds mass and volume. Mass is the amount of matter in an object that is usually explained in the unit of kilograms. Volume is defined as the amount of space that matter takes up usually described by the unit liters. While mass and volume relate to matter, it also relates to density.

Experiment 1: First, fill the Graduated cylinder to 100 ml and pour it into the cup. Then add 58 ml to the cup. Guess the amount of paper clips you think will fit and then add the paperclips and record your information. Example 2: first, fill the cup with 1 ml of soap, then add 100 ml of water, and then stir it. Then add 48 ml. of water and guess the number of paperclips and then do the experiment and record your data.

First, the mole count of water and of the ethanol was measured with the corresponding volume that both occupied in a solution and then their mole fractions were obtained varying to the quantity they occupy. The molar volume of the mixture was computed with the density and the average molecular weight which was then identified with the mole fractions and molecular weights of water and of ethanol. The density of the mixture was measured with the mass in grams of the sample and the volume it occupies. Having the pycnometer weighed with a full amount, the empty pycnometer weight was simply subtracted and yielded the mass of the mixture. Subdividing the average molecular weight with that of its corresponding density gave the molar volume.

2) Then you measure all eighteen cylinders to see what their starting mass is, I will use a set of scales to do this.

Figure 2 The pan balance method for measuring the buoyant force and specific density. METHOD III. (Graduated Cylinder Method) Determine the mass of the empty graduated cylinder and an average mass for the washers. Place about 10 washers in the graduated cylinder, and carefully place the cylinder in the beaker which is about 2/3 full of water. This initial loading with washers should insure that the cylinder floats upright, if not add more washers. Be careful not to have air bubbles under the base of the cylinder. Record the number of washers and volume markings on the graduated cylinder at the waterline as the cylinder floats. Add a washer, and record these values again. Repeat this process of adding washer and recording up to the point of sinking the cylinder. Plot volume marking vs number of washers

4. Determine the difference in the masses and record this mass. This value is the mass of the fluid.

The purpose of this experiment is to determine mass, length, temperature, volume, and density of objects and liquids using common measuring devices and algebraic formulas. The metric system, the most common set of measurements used in science, which includes meters, liters, Celsius, and grams will be used.