Master Chemistry with Fun Quizzes & Brain Teasers!

In the electrowinning process, a Metallurgical/Chemical Engineer uses an Infrared (IR) camera to detect metallurgical short-circuits (hot spots) over the anodes and cathodes. Given that the mass of an electron is 9. 109 1031 and Rydbergs constant is 1. 090107 1 , determine the energy (in MJ) applied when 5 mol of IR photons having a wavelength of 32 nm is used in the copper electrolysis process
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A reaction must be spontaneous if its___ occurrence is thermic with an___ crease in entropy
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How many lead atoms are present in a piece of lead of volume 1. 907 cm?Useful data:The density of Pb = 11. 34 g. Cm-3. Avogadro's Number (NA) = 6. 022x1023 atoms. Mol-1Give your answer to 3 significant figuresGiving your answer with specific significant figures. Use 'e' notation for powers of ten:for example for 1. 23 x 104, enter 1. 23e4for example for 6. 022 x 1023, enter 6. 022e23for example for 1. 23 x 10-6, that is 0. 00000123, enter 1. 23e-6note no gaps
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A) Determine the [OH] of a solution that is 0. 145 M in CO32 ( Kb=1. 8104 ). Express your answer using two significant figures. B) Determine the pH of a solution that is 0. 145 M in CO32. Express your answer to two decimal places. C) Determine the pOH of a solution that is 0. 145 M in CO32. Express your answer to two decimal places
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Unit 6 Critical Thinking Questions! (HELP) - 30 POINTS1. Compare and contrast positive and negative feedback loops of the endocrine system. Provide a specific example of each, including which gland is responsible for the hormone related to that loop. 2. What is the difference between endocrine and exocrine glands in terms of both form and function? Why is one type not considered part of the endocrine system?3. Describe the cascade of events that occurs when blood glucose levels decline, including which organ and cells respond, which hormones are released, and how the process helps maintain homeostasis. Your answer should cover all three ways glucose is re-introduced to the body. What is the ultimate use of the glucose created in this process?4. Why can both type I and type II diabetes, untreated, result in impaired vision or blindness as someone ages? How does type II diabetes turn into type I diabetes as someone ages?5. Imagine you have a patient who has come to you and is exhibiting symptoms such as fatigue and increased thirst and urination. What would you check for to determine whether the patient has Cushings, type I diabetes, or type II diabetes?
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Katja plans an experiment that measures the temperature of different colors of paper placed in sunlight. Her hypothesis is that if black, blue, yellow, red, and white sheets of paper are exposed to white light, then the black sheet of paper will increase the most in temperature. Katja will place a sheet of each color of paper of the same size and thickness in the same location for the same amount of time. Why will katja use different colors of paper in her experiment?
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A mixture of 100 mol containing 60 mol % n-pentane and 40 mol% n-heptane is vaporized at 101. 32 kpa abs pressure until 40 mol of vapor and 60 mol of liquid in equilibrium with each other are produced. This occurs in a single-state system, and the vapor and liquid are kept in contact with each other until vaporization is complete. required:calculate the composition of the vapor and the liquid
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If you start with 29. 25 g of NaOH and 107 g of FeCl3, find the reaction yield and the limiting reactant. Show your work
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Combustion of 13. 5 g of sample of an hydrocarbon yields 24. 41 g CO2 and 14. 49 g H2O. The molar mass of the compound is 246 g/mol. What are the empirical and molecular formulas?
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Part BOne of the main components of an airbag is the gas that fills it. As part of the design process, you need to determine the exact amount of nitrogen that should be produced. Calculate the number of moles of nitrogen required to fill the airbag. Show your work. Assume that the nitrogen produced by the chemical reaction is at a temperature of 495C and that nitrogen gas behaves like an ideal gas. Use this fact sheet to review the ideal gas law. Part CRecall the balanced chemical equation from part B of task 1:2NaN3 2Na + 3N2. Calculate the mass of sodium azide required to decompose and produce the number of moles of nitrogen you calculated in part B of this task. Refer to the periodic table to get the atomic weights
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A gas sample occupies a volume of 155 mL at a temperature of 316 K and a pressure of 0. 989 atm. How many moles of gas are there?2PointsShow your work
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How many grams of oxygen would be needed to completely react with 254 g of tristearin, C57H110O6, by the following reaction: 2C57H110O6 + 163O2 114CO2 + 110H2O
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2AgNO3(ag) + Cu(s)---> 2Ag (s) + Cu(NO3)2 (aq)How many moles of Ag will be produced from 3.50 g of Cu?
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The following reaction is done at stp:n2 (g) + 3 h 2 (g) 2 nh 3 (g)if i.5 l of nitrogen gas are added to an excess of hydrogen gas, how many liters of nh3 gas will form?
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What is the mass (in g) of a solid piece of iron which has a specific heat of 0.449 J/gC if when it absorbed 948.0 J of heat the temperature rose from 24.0C to82.1C? Give your answer in 3 sig figs.
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A 210.00 g sample of water with an initial temperature of 29.0C absorbs 7,000.0 J of heat. What is the final temperature of the water?Note: Use C (capital C) for degrees Celsius when typing units. So it might look like 35C or 2.03 J/gC. Give your answer in 3 sig figs.
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Calculate the cell potential for the following unbalanced reaction that takes place in an electrochemical cell at 25 C when [Mg2+] = 0. 000612 M and [Fe3+] = 1. 29 MMg(s) + Fe3+ (aq) = Mg2+ (aq) + Fe(s)E(Mg2+/Mg) = -2. 37 V and E(Fe3+/Fe) = -0. 036 V
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Calculate the specific heat in J/(gC) of an unknown substance if a 2. 50-g sample releases 12. 0 cal as its temperature changes from 25. 0C to 20. 0C. ________J/(gC)
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How much nitrogen is needed to form 1. 4 mol of ammonia
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Please Help!!!! D:A student runs tests on an unknown substance and discovers the following properties. What other property does this element most likely have?A highly reactiveB low electronegativityC has many isotopesD not found pure in nature
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Several students performed this experiment without paying adequate attention to the details of the procedure. Briefly explain what effect each of the following procedural changes would have ont the size of the volume-to-temperature ratio calculated by the students. A) One student failed to replenish the boiling water in the boiling-water bath as the flask was being heated. At the end of the 6 min of heating, the boiling water in the bath was only in contact with the lower portion of the flask. B) Following the proper heating of the flask in the boiling water, a student removed the flask from the boiling-water bath but only partially immersed the flask in the ice-water bath during the cooling period. C) A student neglected to close the pinch clamp before removing the flask from the boiling-water bath and immersing it in the ice-water bath. D) One student neglected to measure the volume of the flask before leaving the laboratory. Because the procedure called for a 125-mL Erlenmeyer flask, the student used 125 mL as the volume of the flask
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If the bond length in a XY molecule is 212, what will be the covalent radius of atom X, if the covalent radius of Y atom is 93.
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If the concentration of NaCl is 6. 07 M, when it begins to crystallize out of solution, then what is the Ksp
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Assuming pressure is constant. There are 12. 75 mL of chemical product associated with a temperature reading of 68 degrees Celsius. What will the final temperature be if the volume increased to 5. 25 mL
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