Viscosity of Liquids Lap Report

Procedure: I used a ruler, thermometer, and scale to take measurements. I used a graduated cylinder, short step pipet, scale, and ruler to determine volume and density. I used a volumetric flask, graduated pipet, pipet bulb, scale, and glass beaker to determine concentrations and densities of various dilutions.

An automatic pipet was used to measure 0.450 mL water and 0.165 mL acetic anhydride and was added to the conical vial. A spin vane was placed into the vial and an air condenser was attached.

Objective: The main goal of this lab is to learn how separation of binary liquid mixtures is performed. Especially when the two liquids have boiling points varying by about 30° C. Hexane can be separated from toluene in this experiment because of the difference in their boiling points. Since toluene has a higher boiling point, it will left at the bottom while the hexane starts to boil out and collect in the Hickman still. GC measurements help us in determining how accurate our data is by making a graph of the amount of hexane and toluene in each fraction. Also this lab gives experience with semi-micro

A. Water boils at 100°C at sea level. If the water in this experiment did not boil at 100°C, what could be the reason?

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.

In this lab, the molar mass of a volatile liquid is determined based on its physical properties in the vapor state. In order to calculate the molar mass, the mass, temperature, pressure, and volume is measured independently and then converted to the correct units. Sample C was obtained at the beginning of the experiment, which was later informed to be ethanol. Based on the calculations made, the molar mass of the volatile liquid was 95.9 g/mol. However, compared to the known value of 46.1 g of ethanol, the value measured had a 108% error. Unfortunately, this was a very big percent error and may have been caused by incorrectly measuring the volume of the gas. Using the ideal gas law, the molar mass of a volatile compound was calculated in order

A small beaker was placed under the arm of the distillation head to catch the distillate. Foil was wrapped around the neck of the round-bottomed flask and a wet paper towel was wrapped around the arm of the distillation head to create a condenser. The flask was heated gently so that the distillate dropped at a rate of two drops per minute. The temperature was recorded as every drop was collected. The distillation began at around 55.0 ℃. The distillation was stopped after 29 drops were collected to prevent the solution from being distilled to dryness. See attached data. The known boiling point of 1-butanol is 117.5 ℃ (Lemonds). The known boiling point of 1-propanol is 97 ℃ (Thiyagarajan). The known boiling point of acetone is 56 ℃ (Forss). The known boiling point of 2-butanone is 79.6 ℃ (Jiang). For unknown #3 the boiling point of the first substance seemed to be around 56 ℃ and the boiling point of the second substance seemed to be around 111 ℃. Therefore unknown #3 seemed to be a mixture of acetone and 1-butanol.

Corresponding to the previous experiment, this week’s experiment measures the participants’ ability to conduct basic, fundamental laboratory procedures. These procedures revolve around scientific measurements of volume, mass, and density. Unlike last week’s activity, this week’s experiment had a few modifications. In addition to distilled water, saltwater and an unknown substance were added. There was a total of five substances to choose from; Hexane, Methanol, Ethyl acetate, Ethylene glycol, and Dichloromethane. Part C, the unknown liquid number was four, which the average density was 0.789 gmL-1, and from looking at the chart the unknown identity was methanol. Part A, the temperature of the water was 20 oC, which was in front of the class,

In this experiment, 0.31 g (2.87 mmol) of 2-methylphenol was suspended in a 10 mL Erlenmeyer flask along with 1 mL of water and a stir bar. The flask was clamped onto a hotplate/stirrer and turned on so that the stir bar would turn freely. Based on the amount of 2-methylphenol, 0.957 mL (0.00287 mmol) NaOH was calculated and collected in a syringe. The NaOH was then added to the 2-methylphenol solution and allowed to mix completely. In another 10 mL Erlenmeyer flask, 0.34 g (2.92 mmol) of sodium chloroacetate was calculated based on the amount of 2-methylphenol and placed into the flask along with 1 mL of water. The sodium chloroacetate solution was mixed until dissolved. The sodium chloroacetate solution was poured into the 2-methylphenol and NaOH solution after it was fully dissolved using a microscale funnel.

Glycerol standard sample was given to the class. One sample of 3 ml Triglyceride reagent was heated at 37°C for 5 minutes, then mixed with 30 µl of Bos taurus homogenate and incubated for 10 more minutes at the same temperature. Absorbance of the glycerol standard and homogenates were measured, and converted to concentration of glycerol (Clendening).

The purpose of this experiment is to determine the molar mass of an unknown volatile organic liquid, using methods such as, the Dumas method, and then state its identity.

In a test tube, 0.5mL of the sample will be added with 0.5 mL of water and shaken vigorously. Take note for its solubility by parts (0.5mL is one part). Keep adding parts of the solvent until the sample is soluble. If not, add until ten parts of the solvent and determine its solubility. To separate test tubes, water will be replaced with ethanol, chloroform, ether, and acetone as solvents. Same procedures were

iii. Materials: Distilled water, beverages (juice, soda, sport drinks), Sugar reference solutions (0, 5, 15, ad 20%) 25ml each, Balance, centigram(0.01g precision), Beaker (100-mL), Erlenmeyer flask (125-mL to collect rinse solutions), Pipet(10-mL), Pipet bulb or pipet filler

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 10 mL round-bottom flask was weighed both before and after approximately 1.5 mL of the given alcohol, 4-methyl-2-pentanol, was added. 3 mL of glacial acetic acid, one boiling chip, and 2-3 drops of concentrated sulfuric acid were added to the flask in that order. The reflux apparatus was assembled, the