2071 - make up - Recrystallization Thad Tatum

16 16 TTTT Graph 1: Solubility Curve for Potassium Perchlorate (KCIO4) 1000 Concentration (grams/kg H₂O) 900 800 700 600 500 400 300 200 100 0 0 20 BLIVEWORKSHEETS 30 50 60 70 80 Temperature (Celsius) 90 100

4. You'll purify your aspirin product via recrystallization before you can weigh it. The Merck Index indicates that at room temperature, 300 mL of water - but only 5 mL of ethanol - will dissolve 1 gram of aspirin. But the water solubility of aspirin increases with temperature. At 37°C, 1 gram will dissolve in 100 mL of water. Note you'll use a MIXTURE of ethanol and water to recrystallize your aspirin product. a) Why is it essential that you NOT allow the ethanol-water recrystallization mixture to reach a boil? b) And why is it important not to use too large a volume of ethanol in your recrystallization?

Q1. Give three criteria for a good recrystallization solvent. Q2. You want to purify 10 grams of benzoic acid that has been contaminated with 0.2 g of salicylic acid. You are given the following data: Solubility in water at 20 °C Solubility at 100 °C (g/10 ml) Compound (g/10 ml) Benzoic Acid 0.029 0.680 Salicylic Acid 0.680 0.029 0.22 6.67 a) What volume of Boiling water is needed to dissolve the 10 g of benzoic acid? (show calculations) b) How much benzoic acid will crystallize after cooling to 20 °C (show calculations) c) Will any salicylic acid crystals form? Why or why not? (show calculations/ reason for answer) d) What is the maximum amount of benzoic acid that could be recovered in the first crop of this recrystallization? (Show calculations) e) How can you prove the purity and identity of the purified Benzoic acid?

5. Chemical Xis a solid with white color that forms large crystals. The solubility of chemical X in water at different temperatures is shown below. Solubility of X in H20 124 10- 8- 6- 2- 0+ Ó 10 20 30 40 50 60 70 80 90100 Temperature (°C) Irina wants to dissolve 30 grams of Xin 1 liter of water. She does so by stirring 30 grams of the large crystals into 1 liter of water at 45°C. How could Irina change her method to dissolve all the X faster? Solubility (g/100 g H,O) 4-

utions - Homework - 2022.pdf - Adobe Acrobat Pro DC (32-bit) E-Sign Window Help ols Chapter 14 - Soluti. x 2 / 3 135% 8) Determine the freezing point of a solution that contains 63.8 g of naphthalene (C10H8, molar mass = 128.16 g/mol) dissolved in 275. mL of benzene (d = 0.877 g/mL). Pure benzene has a melting point of 5.50°C and a freezing point depression constant of 4.90°C/m. d fliv ebruogrnos sniwollot srb lo rdairlW (1 (EelD) onimaly tomit (I acorous (CH3COCH?) stuloe slitslovn qps adnoone B) O 300 CISO Inioq anilam omce ori overl ls verdT (3 D)0 100 a VICI oqmot eirs s ) vilidulce ort oninnsis (E 0.26 gnivlozaib yd bonisido pexsue Ce ylienob e 26rd noituloe adt it DH arlo inalom srb noituloe 1 MS.0lo (J) omulov torW

Please answer this question as fast as you can please and tahnk you. I will afterwards write an wonderful review on solving the question. Thank you. Why is it important for us to leave the water for 5 minutes and determine the water's temperature? The density of water will vary with temperature. You want the water to equilibrate to room temperature in order to maintain consistent results. You want to wait so that the dissolved solids in the water settle to the bottom of the flask. It is impossible to determine the density of water below 20 °C with plastic beakers and cylinders so you need to wait for the water to warm up. It's not that important, we just want to stretch out the time of the experiment.

José performs an experiment to determine how much sugar can be dissolved in 250 milliliters (mL) of water at 25°C. He adds 50 grams (g) of sugar at a time to the water while stirring and observes the solution After adding sugar the eleventh tene (550 g), he notes that undissolved sugar has settled to the bottom of the container. He stops adding sugar and ends his experiment. In his lab write-up he concludes that the solubility of sugar in water at 25°C is 500 g per 250 ml. is his conclusion defensible, and why or why not? O No, because he did not add sugar enough times. Yes, because when he added more than 500 g it did not all dissolve. O No, because he does not know if any of the final portion of sugar dissolved. O Yes, because when he added the tenth portion (500 g) all of it dissolved.

A sample of rainwater was collected from four separate locations across theMetroplex. Each sample was measured once by two separate methods for the presence ofsulfate. Determine whether the two methods are equivalent with respect to giving thesame answer for [SO42-].

A group of third-year students, who had been growing chilli peppers at home, decided to bring samples to their Pharmacology practical where they would be measuring capsaicin, to determine which of them had grown the hottest peppers. The three students ground a sample of their peppers in 100 µl of distilled water, centrifuged the solution and then transferred the supernatant into a collection tube. One student used 70 % ethanol from a wash bottle on their bench instead of using distilled water as the extraction fluid. Samples of the collected supernatants were added to a 96 well test plate along with a range of serially diluted capsaicin standards. The students used a FlexStation which automatically added 20 µl aliquots of each supernatant onto separate wells containing 80 µl of cultured cells, which had been transfected with the capsaicin sensitive TRPV1 ion channel and preloaded with the ratiometric calcium indicator dye FURA-2 prior to the class. The FlexStation was programmed to…

A 20ml mixture contains 10% volume methanol and 90% volume water. Find the mole fraction of water and methanol

Part II. Determination of molecular weight for ethyl alcohol Freezing point, °C DTf   Mass of solute, g mass of solvent, kg Calculated molecular weight, g/mol -2.30 0C ΔTf = T0f – Tf 0.0 °C -(-2.30 °C) = 2.30 0C 6.202 g 0.1kg Click or tap here to enter text.

逐步解决 不使用人工智能出色完成工作 非常感谢您的支持 SOLVE STEP BY STEP IN DIGITAL FORMAT DON'T USE AI | DON'T USE AI | DON'T USE AI | DON'T USE AI | 2. An ethyl alcohol solution that is 75% alcohol by weight is to be used as a bactericide. The solution is to be prepared by adding water to a 95% ethyl alcohol solution. How many grams of each should be used to prepare 400 grams of the bactericide?

Data Sheet 4 ble gives the recommended mass of salt to dissolve in each of the four test tubes. Show a sample calculation for the solubility of KNO, using your actual mass from tube #1. Complete your graph on the back of this sheet. Solution # Recommended mass KNO3 Actual mass of KNO, (g per 5 mL H₂O) Solubility & KNO, 100 g H₂O Saturation temperature (°C) (g) 1 2.0 51.3 2.1971 2 62.5 4.0 11.1568 3 72.7 6.0 6.0112 83.6 4 8.0 806 Sample Solubility Calculation: Questions 1. According to your data, how does the solubility of KNO, change with increasing temperature? Does this indicate an endothermic or exothermic dissolving process? Explain. 2. Using your graph, indicate if each of these solutions would be saturated or unsaturated: a) 110 g of KNO3 in 100 g of water at 40 °C b) 60 g of KNO3 in 100 g of water at 70 °C c) 140 g of KNO3 in 100 g of water at 60 °C 3. According to your graph, what mass of KNO3 will dissolve in 100 g of water at 30 °C?

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Which two chemicals make up the 50/50 fractional distillation and which two make up simple distillation based on the the data given and why can be 2 of the following. Ethanol, acetone, toluene. And why is those two and not the other and what temps tell you that is those to chemicals.

I need a quick solution within 5 minutes With my best wishesTon

4. To set up your seed assay, you’ll conduct serial dilutions of a fuel derived from a renewable feedstock. To begin, you’ll make 20 mL of a 10% solution of your assigned fuel. a. How many grams of fuel will you need to make your solution? Hint: The definition of a 10% solution is 10 grams of solute (fuel in this case) in 100 mL of solution. b. You will then pour 10 mL of your 10% solution into an empty beaker. How much water (in mL) should you add to the beaker to create a 5% solution? Hint: Assume all of your fuel is completely dissolved and the volumes of the solutions are additive.

TOPIC: Recrystallization Students were tasked to conduct a recrystallization experiment to test the ability of the three newly discovered solvents in their laboratory to purify and separate a mixture containing compounds X and Y. The solubilities of the two compounds in g/50 mL of hot and cold solvents are given in the table. Given the data, if a mixture containing 9.0 g each of X and Y is to be recrystallized from 100 milliliters of the solvents, what is the best solvent to use? Support your answer by doing a schematic diagram for EACH solvent.

Grams of solute/100g H 20 150 140 130 120 110 100 90 80 70 60 50 40 30 20 10 0 KI Na2SO47 0 10 Solubility Curve NaNO3 HCI NH3 KNO3 NaCl gases solids NH4CI KCI KCIO3 SO2 20 30 40 50 60 70 80 90 100 Temperature (°C) 1) Find the solubility of potassium nitrate at i) 20 °C, ii) 80 °C 2) Calculate the maximum amount of potassium nitrate that could be dissolved in 20 cm³ of water at 40°C. 3) Find the minimum temperature needed to make a solution of potassium nitrate with a concentration of 2.0 mol dm-³. 4) Compare and contrast the solubility curves of sodium chloride and sodium nitrate 5) Summarise the trends in the solubility curves for solid salts and gases.

Concentration of Acetic Acid in a Vinegar Solution. Average molarity of NaOH Volume HC₂H30₂ sample Final buret reading Initial buret reading Volume NaOH (Show all units and all calculations) Molarity of HC₂H30₂ (unrounded) Average molarity of HC₂H302 (unrounded) Deviations Average deviation Best estimate for molarity of HC₂H302 Average mass percent HC₂H302 46.4mL Oml Ran out of Base ↓ ↓ ↓ ↓ 10.014 HOA je beart giov isults weari?! ferottelucuny Cambia) 10 Kousad Question 1. A Rolaids tablet contains calcium carbonate that neutralizes stomach acid. If 44.55 mL of 0.448 M hydrochloric acid is required to neutralize one tablet, how many milligrams of calcium carbonate are in a Rolaids tablet? CaCO, (s) + 2HCl(aq) → CaCl₂ (aq) + H₂O (1) + CO₂ (g)

Examine the solubility chart below and answer questions 5-12 300 Sugar 260 KNO 220 - * 180 140 NaBr 100 KBr 60 KCL Naci 20 Ce,(so 20 40 60 80 100 Temperature ("C) 5 hi ost soluble in water at 0°C? 5. D. NaBr E. Ce2(SOa)3 6. Whir st soluble in water at 50°C? 6. D. NaBr E. Ce2(SO4)3 7. Which innic soluble in water at 60°C? 7. D. NaBr E. Ce2(SO4)3 8. WLinh i - st soluble in water at 70°C? 8. D. NaBr E. Ce2(SO4)3 9. Which ionic solid is most soluble in water at 80°C? 9. A. sugar (C12H22011) B. KNO3 C. NANO3 D. NaBr E. Ce2(SO4)3 Solubility (g solute per 100 g H,0)

Materials Needed solid I2 solid CUSO4-5H20 food dye solid (NH4)2SO4 heavy metals waste container halogenated waste container non-halogenated waste container semi-micro test tubes and rack regular test tubes and rack squash pipettes acetone cyclohexane propan-2-ol Method Part A: Solubility of ionic and molecular solids 1. Place a small amount (about the size of 1 grain of rice, see picture) of copper sulfate into each of three DRY semi-micro test tubes. Add 20 drops of water to the first test tube and gently flick the test tube with your finger to ensure mixing. 2. Repeat step 1 using acetone in place of water as the solvent in the second test tube. 3. Repeat step 2 replacing acetone with cyclohexane in the third test tube. Hold the test tubes against a white background to compare the solubility of copper sulfate in the three solvents and record your results. Discard these mixtures into the heavy metals waste container in the fume cupboard. Once these test tubes have been emptied you…

Place 2.4 grams of sulfanilic monohydrate in a 125 ml Erlenmayer flask and dissolve it in 25 ml of 25% aqueous sodium carbonate by boiling. Cool the solution in the flask with running water before adding 0.95 gram of sodium nirite with stirring to dissolve the solid. Pour the solution into a 50 ml Erlenmayer flask containing 12.5 grams of ice and 2.5 ml of concentrated hydrochloric acid. Within a few minutes the white diazonium sulfonate inner salt should form a suspension. Transfer half of it to a 100 ml beaker, and keep both containers cold until each is used in later steps.  Identity test used is ________ Reagents used are ___________ MOA _____________ Product ____________ Visible result ____________

Place 2.4 grams of sulfanilic monohydrate in a 125 ml Erlenmayer flask and dissolve it in 25 ml of 25% aqueous sodium carbonate by boiling. Cool the solution in the flask with running water before adding 0.95 gram of sodium nirite with stirring to dissolve the solid. Pour the solution into a 50 ml Erlenmayer flask containing 12.5 grams of ice and 2.5 ml of concentrated hydrochloric acid. Within a few minutes the white diazonium sulfonate inner salt should form a suspension. Transfer half of it to a 100 ml beaker, and keep both containers cold until each is used in later steps.  Reagents used are ___________ MOA _____________ Product ____________ Visible result ____________