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Lab 20: Solubility: A Guided Inquiry Lab

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    During the Solubility Lab,  my partner and I identified an unknown salt. The purpose of this lab was to design a procedure that determines the identify of the unknown salt. In the lab, we dissolved different amounts of the unknown salt with 10 mL of water at different temperatures. Dissolving is the process in which molecules interact and attract each other to form a solution. Procedure -    First, we measured 100 mL of water in a beaker and increased the temperature from 20°C to 50°C using a hot plate. Then, we measured 5 g of the unknown salt on a balance. After that, we added the unknown salt to the to the water. All of the solute dissolved into the water. Realizing we made the mistake of having 100 mL of water instead of 10 mL of water, we measured 10 mL of water and increased the water temperature to 50°C. We added 5 g of the unknown salt. Only 3.9 g out of 5 g dissolved in the 10 mL of water. We concluded that the unknown salt was NaCl because 3.9 ...

Lab 18: Gas Law Lab

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   In the Gas Law Lab, we collected gas in a balloon that was given off by a powdered form of two Alka Seltzer tablets. We were able to do this because  the sodium bicarbonate (NaHCO 3 ) and citric acid (C 6 H 8 O 7 ) dissolved in the water (H 2 0) and produced carbon dioxide (CO 2 ). After that, we used the ideal gas law to determine the mass of the carbon dioxide (CO 2 ). Calculations Analysis Questions 1.  Discuss an area in this lab where experimental error may have occurred.    Experimental error could have occurred when some water might have spilled out when my partner and I were measuring the volume un the graduated cylinder. The balloon is not a perfect sphere. The measurement of the circumference.  could have been miscalculated. 2. Choose one error from above and discuss if it would make "n", the number of moles in  carbon dioxide (CO 2 ), too big or too small.    The first error  would m...

Lab 16: Specific Heat of a Metal

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   In the Specific Heat of a Metal Lab, we uncovered the identity of an unknown metal by determining the specific heat of the metal. First, we heated a beaker filled with water to 90°C with the unknown metal inside. Then we inserted the metal into a container of 22°C water. After a couple of minutes, the water's temperature increased to 26°C. We used the heat gained by the 22°C water to determine the specific heat of the unknown metal. Calculations Heat Gained By Water Specific Heat of Unknown Metal Unknown Metal Specific Heat 323 J            Brass Specific Heat - 380 Unknown Metal = Brass Percent Error - 14.8%  Sources of error could have came from heat escaping the hole that the thermometer punched through the styrofoam cup container and the heat lost from taking out and placing the unknown metal into the new container of water.

Lab 15: Evaporation and Intermolecular Attractions

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   In the Evaporation and Intermolecular Attractions Lab, we found the change in temperature of four different substances by evaporating the substances. We used a LabQuest device to record the temperature of each substance while it was evaporating for 240 seconds. First, we wrapped the LabQuest probe in filter paper. Then we soaked the probe in one of the four substances for thirty seconds. After that, we set the probe on the table to evaporate and collect data.  Calculation Questions 2. Explain the differences in the difference in temperature (𝝙𝗧) of these substances as they evaporated. Explain your results in terms of intermolecular forces.    Due to each substances' different intermolecular forces, they all had varying changes in temperatures. For example, Methanol had the greatest value in change. This was due to its relatively weak intermolecular force compared to those of the other four substances. Therefore, it evaporated and c...

Lab 14: Ester Synthesis

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In the Ester Synthesis Lab, my partner and I synthesized chemical compounds that produced  different smells. We mixed ten drops of three different alcohols with glacial acetic and concentrated sulfuric acid in three test tubes. Then we submerged the test tubes in 70 °C water (H 2 O) for ten minutes. After ten minutes, we smelt the three solutions. Analysis Questions 1. Compare odors of the three mixtures after heating compared to the odors of the starting materials. How are the different?    Before heating, all the mixtures smelled close to cleaning supplies. After heating, the mixtures smell sweet. 2. Based on the smell of the mixture after heating, what functional group must be present in the final molecules that were produced? Draw it.    Ester is present in the final molecule that was produced. 3. Were the new compounds easily identified as a specific fragrance like apple or banana? In the case where a specific fragrance was detected, how doe...

Lab 12: Electron Configuration Battleship

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   In the Electron Configuration Battleship game,  I calculated electron configurations with the four different blocks on the periodic table. The biggest challenge I had was locating the electron configuration ships and determining the electron configurations for f-block. The game required my partner and myself to recite electron configurations of certain elements to take down battleships.

Lab 11: Flame Test Lab

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   During the Flame Test Lab,  metallic ions were burned and vaporized to exhibit specific colors. Nine solutions and two unknown solutions were burned and displayed colors ranging from pink to blue. Pre-Lab Questions 1. What is the difference between ground state and excited state?    When an atom is in its ground state, it is in its lowest but stable energy level. When an atom is in its excited state, an electron has jumped from its orbital level to another one. 2. What does the word "emit" mean?    Emit means to produce or release something. 3. In this experiment, where are the atoms getting their excess energy from?    The atoms are getting excess energy from the heat. 4. Why do different atoms emit different colors of light?    The atoms emit different colors of light because the energy that was absorbed from the heat emits electromagnetic radiation at different wavelengths. Data Analysis ...