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Titration

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Summary In this lab, students were given the task of finding the percent ionization of the acetic acid, CH3CO2H, in vinegar. Students would slowly add in sodium hydroxide, a base, into the acetic acid until it was neutralized, and showed a pale pink. Materials included a funnel, a burette, beakers, a hot plate, an Erlenmeyer flask, a graduated cylinder, a pippette, and a magnetic stir bar. Data Percent Ionization of Vinegar Our percent ionization of vinegar is 0.45% . This is such a low number because it is a weak acid, so the molecules doesn't seperate easily, and so not all of them split into ions. Photos Our setup Trial #1 Analyte (Failed) Trial #2 Analyte at Equivalence Point

Solubility: A Guided Inquiry Lab

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Introduction The purpose of the lab was for students to, using a given graph of solubility, decipher whether an unknown substance is NaCl, NaNO2, or KNO3. Students were not given a procedure, so they had to design their own. Materials included beakers, a hot plate, a balance, a thermometer, a graduated cylinder, and a stirring rod.  Solubility- ability for a solute to dissolve in a solvent Solubility Curve- a graph of the variation of changing temperature of the solubility of a given substance in a given solvent Solute- smaller component of a solution that is dissolved into a solvent Solvent- larger component of a solution that dissolves the solute Solution- liquid mixture where the solute is evenly dispersed in the solvent Saturated Solution- solution containing the maximum concentration of a solute dissolved in the solvent Our Set-Up Procedure 1) We first obtained materials: beakers, a hot plate, a balance, a thermometer, a graduated cylinder, an...

Gas Law Lab

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Summary In this lab, students were given a two tablets of Alka Seltzer and were told to collect the CO2 gas it gave off. The crushed Alka Seltzer powder mixed with water would cause the balloon to inflate, then measuring the circumference of the balloon using a string. Then, using the ideal gas law and finding the volume of the sphere, students could determine the mass of the gas. Data Table and Calculations  Analysis Questions 1) When we were transferring the water from the balloon to the graduated cylinder, some water splashed out. Also, while we where measuring the circumference of the balloon with the string, it wasn't perfectly in the middle. 2) The error from the above question of losing water while transfering it would cause the number of moles of CO2 to be too large. This is because the volume of the water that fits in the balloon would be greater, and therefore when you solve for the amount of moles of CO2 in the ideal gas law, it would turn out larger....

Specific Heat of a Metal

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Summary In this lab, students were asked to design a procedure to determine an unknown metal's specific heat in order to identify the mystery metal. Each group was given two styrofoam cups (one small one big), water, a thermometer, tongs, and a beaker. Our group decided to measure the specific heat by heating the metal in boiling water, then place it into cool water, and see the temperature difference. The difference would explain the metal's gain of energy and heat.  Set Up Procedure 1) Obtain the materials. Set up and start heating the the hotplate, and place a beaker filled with water onto the plate. Poke a hold into the middle of the small styrofoam cup.  2) Mass the unknown metal sample. 3) Mass the large styrofoam cup, mass the large cup filled with water, and then subtract those to get the mass of the water itself. Take the initial temperature of the water in the styrofoam cup. 4) Gently place the metal into the beaker. 5) When the w...

Evaporation and Intermolecular Attractions

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Pre-lab and Data Tables Calculations and Results 2) Explain the differences in the difference in temperature of these substances as they evaporated. Explain your results in terms of intermolecular forces. There are differences in the temperature of the substances as they evaporated is because of the different heat absorptions. In order to change a liquid to a gas, you must have enough energy to break the intermolecular bonds of the liquid. As the liquid evaporated into gas, it absorbs energy, in the form of heat, from the temperature probe. When the substance absorbed in the filter paper was evaporating, whether the drop of the temperature would be drastic or mild was due to how much energy was needed to break the intermolecular bonds.   3) Explain the difference in evaporation of any two compounds that have similar molar masses. Explain your results in terms of intermolecular forces.  The difference in evaporation of any two compounds that have similar ...

Ester Synthesis

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Summary In this lab, the students were asked to combine substances of acids and alcohols and notice the differences of the smells. From this, the students learned how molecules can be changed into different molecules using chemistry.  Students were given three test tubes, labeled I, E, and M. In test tube I, students placed in 10 drops of isopentyl alcohol, 10 drops of glacial acetic acid, and 1 drop of concentrated sulfuric acid. In test tube E, students placed in 10 drops of ethyl alcohol, 10 drops of glacial acetic acid, and 1 drop of concentrated sulfuric acid. And in test tube M, students measured in 0.15 g of salicylic acid, 12 drops of methyl alcohol, and 3 drops of concentrated sulfuric acid. The students were asked to record the smell of all the substances into a data table.   Our test tubes reacting inside the hot water Data Table Analysis Questions 1) The odors of the three mixtures after heating are sweeter compared to before heat...

Electron Configuration Battleship Lab

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What was the biggest challenge you had while playing? The biggest challenge I had while playing was trying to say the electron configuration for Au, or gold. What was one thing you learned through playing? One thing I learned through playing is how to do the electron configuration for Au, and also how to strategically place "battleships" using reverse psychology to have my opponent not be able to guess where they were placed. Our ending boards