We also collected an accurate amount of acidified water, used to start the reaction. Everything before that point was done with accuracy so we believed it would be a successful experiment, however, we encountered a small problem while swirling the reactants in the”R” tube. The directions stated to swirl untill the solution is in room temperature and we followed this rule but other groups swirled until they saw the reaction getting to a pale yellow. We put the solution over the bunsen burner while it was still pretty brownish in color. For our second experiment, we did not repeat this possible mistake.
I believe we did our procedures accurately. The precipitate was Zinc hydroxide which is amphoteric in nature. Meaning it can react both with acid and base to form salt. We got a white precipitate of zinc hydroxide and it reacted to make salt with both the base sodium hydroxide and the acetic acid. Our result would have been clearer to observe if we centrifuged it long enough because we might have lost some of the precipitate while washing it since it was not centrifuged long enough.
Experiment Colligative Properties & Osmotic Pressure Karen Curry 1/19/2014 1:00pm Abstract The purpose of this experiment is to understand and compare the difference of the freezing points between pure solvents in a solution and a non-volatile solute. Secondly, osmosis is demonstrated in a permeable membrane in this case a dialysis tubing and a less permeable membrane with a much harder shell like the egg. Experiment and Observation Starting with Part I of this experiment I gathered together all my items I needed. Small rubber band, salt, tap water, distilled water, 1/8 teaspoon measuring spoon, crushed ice, beaker 100 mL plastic, stopwatch-digital, test tube 13 x 100 mm, digital thermometer, well plate-24. First I made a water bath by filling the 100 mL beaker with cool tap water.
Kool- Aid Dissolving Latent Lab Introduction In this latent lab the class tested to see how kool- aid capsules would react in different Temperatures of water. The purpose of this lab was to see how viruses react when they enter into a cell. There were many principles used for this particular lab. The hypothesis drawn was that The Kool- aid capsules would dissolve faster in the hotter water. This hypothesis was chosen because it’s easier to digest hot water than it cold.
To do this, the metal will be heated, and then put into water to determine the heat transferred. The heat that is transferred from the metal to the water is measured using the equation: Eq. 2 q(water) = -q(metal) The heat of water is positive because it was initially cold, and because the hot metal was being added to it, it gained heat. The heat of the unknown metal is negative because of the loss of heat it is experiencing when submerged in cold water. The specific heat constant for water, 4.184 J/g C, is used for this equation.
The R tube will then be put in a large beaker. Another large test tube, boiling tube will be needed, along with a Pasteur pipet. A regular sized test tube will be labeled “C” for “colored solution,” and the new boiling tube will be labeled “P” for “product”. One boiling chip will then be placed into the P tube. 5mL of acidified water will be measured, using a graduated cylinder, and will be transferred to the R tube, and will be immediately vigrously mixed with the reactants.
Decant(ing): Decanting is a way of separating a solid from a liquid. We can carefully pour a liquid from a solid, provided the solid is quite dense and resides on the bottom of a container. The easiest way to accomplish this is to hold a glass stir rod against the lip of the container containing the solid and liquid, and gently pour the liquid down the stir rod into a new container. Extraction: Extraction is a way to separate two components with different solubilities, that is, extract one chemical from another. Extraction relies on a principle called serial dilution.
The level of osmotic pressure is equal in the intracellular fluid, and the extracellular fluid.’ (Study.com, 2015) ‘Osmotic pressure is vital within the human body because it allows water to enter a cell if there is lack of water, and vice versa, if there is too much water within one cell, the osmotic pressure will allows the electrolytes to exit a cell.’ (Study.com, 2015) ‘Intracellular fluid has important functions, it transports food within the cells, it also brings waste products from the cells so that they can be picked up and excreted from the body, and it maintains the shape and size of the cell.’ (Nursing411.org, 2015) ‘Extracellular fluid is located outside the body cells. The extracellular fluid consists of one-third of the water contained in the body. The extracellular fluid has many functions; it carries nutrients and oxygen to the body cells and waste materials from the cells. There are two types of extracellular fluid, including interstitial fluid and intravascular fluid.’
This experiment served as a test of our individual laboratory skills in carrying out several chemical transformations involving copper. To recognize that change of state, change in color, formation of a precipitate, or the evolution of heat are associated with a chemical change; to study reactions of copper. The experiment was successful in that the percent yield was reasonable, however we were not able to recover our copper sample with maximum efficiency ( we ended up with an excessive amount ). INTRODUCTION The purpose of the experiment is to cycle solid copper through a series of five reactions. At different stages of the cycle, copper was present in different forms.
Colligative properties can be described reasonably well by a simple equation for solutions of non-electrolytes. The “abnormal” colligative properties of electrolyte solutions supported the Arrhenius theory of ionization. Deviations from ideal behavior for electrolyte solutions led to the determination of activity coefficients and the development of the theory of interionic attractions. The equation for the freezing point depression of a solution of a non-electrolyte as a function of molality is a very simple one (as you may remember from GEN CHEM): Δ TF = K F m (1) The constant KF, the freezing point depression constant, is a property only of the solvent, as given by the following equation, whose derivation is available in many physical chemistry texts1: ( ) o 2 MW(Solvent)R TF KF = 1000 Δ H F (2) In equation (2), R is the gas constant in J/K*mol, TFo is the freezing point of the solvent (K), ΔHF is the heat of fusion of the solvent in J/mol, and the factor of 1000 is needed to convert from g to kg of water for molality. For water, KF = 1.860 o/molal from the