Essay Molar Mass of a Volatile Liquid Lab

I. LIQUID - Identification of an Unknown Liquid: Using the physical properties of Solubility, Density, and Boiling Point.

The measuring cylinder was then used to accurately measure out 20 mL of water, which was then poured into the test tube that would be used for the experiment. The test tube was then placed into the clamp, which was then adjusted in order to make sure that the test tube was grasped firmly and would not fall out.

7.The air dried filter paper was then placed on the weighing scale and results were recorded

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.

tube was placed inside, then another test tube with an equal amount of substance would be placed

Fill a test tube about 1/3 full with cold tap water for use in step 34.

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.

4.Measure 35mL of warm water and add them into each of the 4 test tubes at about roughly the same time. It is essential that the water is warm. Do not seal the test tube.

The weight of each 50ml beaker (used for weighing the mass of dissolved Potassium chloride after the evaporation of water) should be recorded. If the experimenter were to weigh the mass of one beaker and take it as a default mass, the latter may be a source of error.

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.

1 ml of water should be added to the first test tube and make a note. In the second test tube, 1 ml of methyl alcohol should be added. In the third test tube, 1 ml of hexane must be added. Lastly, the fourth test tube will be a control.

The purpose of this experiment is to identify an unknown substance by measuring the density and boiling point. I will be able to conclude which substance is my own from a list of known options stating what its real boiling point and density is.

A volumetric pipette & measuring cylinder can be calibrated by just weighing the water they deliver. As for volumetric flask, the weight of an empty flask is recorded. Next, weigh the flask after filling it with water to the mark.

8.After 5 minutes, remove test tubes from the water bath set in test tube holder and record results. Also turn off hot plate.