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Borax Crystallization LabNAME: _______________________________Purpose: To precipitate crystals when the temperature of a solution is decreased over time. Materials: Borax, Beaker, Thermometer, Water, String, Wood Splints, Pipe Cleaners, and HotplatePre Lab Questions:Is dissolving a chemical or physical property and explain why? ___________________________________________________________________________________________ ______________________________________________________________________________________________________________________________________________________________________________________What is a saturated solution? _______________________________________________________________ ___________________________________________________________________________________________How do you know, using qualitative evidence (what you can see), that a solution has been super saturated? _________________________________________________________________________________ ______________________________________________________________________________________________________________________________________________________________________________________Procedures:Day 1Get the material listed above. Read through the procedures and create your own data table. Safety: Borax is harmful is swallowed, inhaled, or contacts eyes. It is uncommon, but possible, for borax to cause skin rashes. If this occurs tell your teacher immediately. No long sleeve shirts and all hair is tied back. Google on at all times. Write your block and group number on your beaker using a marker and masking tape. Shape your pipe cleaner into a school appropriate shape. Tie the string to the end of the pipe cleaner shape. Tie the other end of the string to the wood splint. When the wood splint is sitting flat on top of the beaker, the pipe cleaner shape should not touch the bottom or sides of the beaker (test this!!). Measure the mass of the wood splint-pipe cleaner shape combination and record Measure __________ mL of water using a graduated cylinder and pour into the beaker. This should be enough to cover the pipe cleaner shape. Place the beaker on the hotplate and turn on high. Do not let the water pass 95.0 °C.At about 85.0 °C , place enough Borax in the water, so that there is a slightly supersaturated solution once the Borax is dissolved in the water. Continually have one person stirring with the thermometer while the other group mates are keeping track of how much Borax has been poured into the water. Record the total number of grams of Borax here: _______________Once you have a slightly supersaturated solution, place the wood splint-pipe cleaner shape combination in the beaker. TURN OFF the hotplate and let the beaker sit on the hotplate until it is cool enough to touch. Once the beaker is cool, place to the back of the lab and let it sit overnight.Clean Up: Unplug the hotplate and clean off the lab stations. Any Borax that was not used needs to be placed in the designated spot by your teacher. Day 2Safety: Borax is harmful is swallowed, inhaled, or contacts eyes. It is uncommon, but possible, for borax to cause skin rashes. If this occurs tell your teacher immediately. No long sleeve shirts and all hair is tied back. Google on at all times. Carefully take the wood splint-pipe cleaner shape combination out of your beaker and place on a paper towel. Take an observation of the crystals and draw a diagram of your crystals. Take the mass of the wood splint-pipe cleaner shape combination with the crystals using the triple beam balance. Find the mass of just the crystals that have precipitated out onto the pipe cleaner. Clean Up: Place the pipe cleaner and crystals in a designated spot by your teacher. Clean out the beaker and store on the drying rack. Clean the lab stations. Extension Questions:What is the molarity of your solution?By heating the water and dissolving the Borax, you are able to dissolve more Borax than what is normally possible at room temperature. When the solution cools back down to room temperature what type of solution has formed? ________________________________________Sugar Article Questions: Read the article attached and answer the questions below.Describe the dissolving process of sugar. (3 sentences min) _________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________ Based on the article, define a dynamic equilibrium. Use context clues! __________________________________________________________________________________________________________________________________________________________________________Create a simple set of procedures that would let you make cotton candy. List the steps below. How do sugar crystals form and what causes them to have different size crystals. What types of candy can be made from different crystal sizes? _________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________Research: When a solution has time to cool they will tend to have larger crystals and when they cool fast the crystals are smaller and more uniformed. Using this information, explain why granite and obsidian rocks look so different, but are still both considered igneous rocks. How does their location on the Earth affect the way they form? How do the rocks differ from each other? Where are they most commonly found? Follow the requirements below to receive full credit. Create a contrast diagram of granite and obsidian rocks. Each rock should have a total of 5 differences from the other rocks.Write a 5 sentence paragraph answering the questions in the prompt.Research/Draw a diagram of the two rocks. Point out two of the rocks differences. The pictures should be clearly stated and the differences pointed out. Cite your sources. All work should be done below. ................
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