Cloud Point and Pour Point Determination

After each of the solids were completely dry, each was placed into a MelTemp device. The temperature at which each solid began to melt and completed melting was recorded.

melting produced a drop in pipette readings. For each gram of ice that melted, the volume change

Contrails also require temperatures lower than minus 76 degrees Fahrenheit, and humidity of 70%, because of these low temperatures the hot exhaust from the engine flash freeze into a thin trail of ice. This vapor condenses into, “an artificial cloud for all intents and purposes.” (Wickson)The high temperatures of the exhaust hold the water in a vapor state until it combines with the cold air around it. The puffy plumes arching over the sky were unlike any contrail most people had seen, because instead of disappearing like usual these crossing trails grew and merged. “Looking toward the San, Aubuchont saw what appeared like an oil and water mixture reflecting a prismatic band of color.” (Thomas) Samples from California’s Lake Shasta and Pit River arm tributary were examined in a lab after weeks of flyovers. These tests have revealed 4,610,000 parts per million of aluminum, 4,610 time the maximum containment level. The thought of spraying fine particles of aluminum seemed utterly strange at first, but after some research they learned that this was considered necessary decades ago. “In fact the idea of spraying aluminum oxide from jet aircraft was patented by Hughes aircraft in 1990.”

3. Turned off the laboratory burner and observed the properties of the product in the evaporating dish.

The unknown sample was then heated in boiling water in step 5. The reason for heating the

In determining the melting point range of the aspirin, a capillary tube (sealed at one end) was one-third-filled with the dried aspirin. The capillary tube and a thermometer were immersed in an oil bath. The temperature at which the solid started to melt and the temperature when the entire sample was completely liquefied were recorded as the melting point temperature range.

Techniques and equipment used throughout the experiment include a reflux apparatus, separatory funnel for isolation, vacuum filtration, and simple distillation. The reflux condenser is used to allow thorough distillation of the product with the use of heat to accelerate and stir while vapors

Clouds to form in the atmosphere have to have water vapor present. This water vapor makes up a cloud. The water vapor in the atmosphere comes from evaporation or deposition. Also the temperature of the air is below the dew point. When the water is fully saturated, it starts to rise and the expansional cooling process begins. During the process of condensation, the aerosol particles act like a nuclei in the atmosphere, which began to grow, creating ice crystals that are big enough to produce a cloud.

In order to fulfil the labs purpose, the lab was split into two parts. The first part consisted of measuring and determining the freezing point depression of the solution water. The second part consisted of measuring and determining the freezing point depression of a solution that consisted of water and an unknown solute.

The purpose of this lab is to separate a mixture and determine the percentages of each of the ingredients. Each substance will have a different boiling point due to its intrinsic properties and from that, we will be able to determine the purity of different products as we evaporate off the next level of product.

Distillation of the first product began at 83 °C. A Pasteur pipette was used to remove 1-ml of the distillate into a vial. A second vial was filled with distillate until it reached 1-ml. As the second vial is being filled, observe the temperature and remove the apparatus from the heat source if there is an observed drop in temperature.

When you pour oil into the water the oil separates from the water as bubbles and floats to the top and looks like a film on top of the water.

Condensation As the evaporated water vapor gets colder rising into the atmosphere, it changes back into different levels of liquid clouds of different types.

The pipette was used to transfer 8 mL of the 0.5 molarity solution into the graduated cylinder. Distilled water was added to raise the bottom of the meniscus to the 20.0 mL line and the solution was transferred into the beaker after it was rinsed with the solution. The pipette was used to take a small quantity of the solution and rinse and then fill a test tube with the solution. The amount of 0.2 molarity solution needed to create 20.0 mL of 0.1 molarity solution was calculated as 10.0 mL. The pipette was used to transfer 10.0 mL of 0.2 molarity solution into the graduated cylinder and distilled water added until the bottom of the meniscus reached the 20.0 mL line. The solution was transferred to the rinsed beaker and then a portion placed into a test tube that had been rinsed with the solution. The amount of 0.1 molarity solution required to create 20.0 mL of 0.05 molarity solution was calculated to be 10.0 mL. The pipette was used to transfer 10.0 mL of 0.2 molarity solution into the graduated cylinder and distilled water added until the bottom of the meniscus reached the 20.0 mL line. The solution was then placed into a beaker that had been rinsed with the solution and then into a rinsed test

Brittain, C. G. (2009). Using Melting Point to Determine Purity of Crystalline Solids. Retrieved from http://www.chm.uri.edu/mmcgregor/chm228/use_of_melting_point_apparatus.pdf