2. A small immersion heater was used to heat water in an insulated cup. The heater was placed in 100.0 gof distilled water initially at 21.0°C, and turned on for 60.0 seconds while the water was stirred with athermometer. The final temperature of the water was measured to be 37.5°C. Assume the specific heatcapacity of the water is 4.18 J/g °C.(a) Calculate the total heat energy in joules absorbed by the water and the average power in watts(1 watt = 1 joule/s) delivered by the heater.The heater was used to deliver 3000 joules of energy to 100.0 g of methanol (CH,OH(E)) in the samemanner. The temperature of the methanol increased by 11.8 Celsius degrees.(b) Calculate the specific heat capacity of the methanol liquid.(c) (i) Calculate the mass of water (H,O, Co= 4.181 Jgl °C-) at 20.0°C that would be requireć%3Dto cool a 30.0-g block of copper (Cu, co0.385 J gl °C-l) from 50.0°C to 25.0°C in aninsulated cup.%3D(ii) Which liquid, water or methanol, would be more effective as a cooling agent for hot metal?That is, which liquid would require less mass to achieve the same amount of cooling?Justify your answer in terms of the quantity of heat required and/or the definition of specificheat capacity.A student wishes to make a solution of potassium hydroxide, (KOH, M=56.11 g/mol) in methanol, ameasure the enthalpy of dissolution of the solid. The student weighs out 4.00 g of KOH(s) and 100.0of CH,OH(e), carefully adds the KOH to the CH,OH in an insulated cup with stirring, and measures :temperature rise of 12.0 Celsius degrees.(d) Calculate the enthalpy change in kJ/mol for the dissolution reaction of KOH(s) in CH,OH(8)described above and represented below. Assume the specific heat capacity of the final solution is2.23 J gl °C-. Express your answer with the correct sign and units.KOH(s) → K*(in CH,OH) + OH-(in CH,OH)(e) Calculate the molarity of the KOH(in CH,OH) solution made in part (d) above. Assume thedensity of the final solution is 0.795 g/mL.Unau

Answered: Image /qna-images/answer/bcacd07f-0352-4d48-bc68-8aa966e770f2.jpg

Calculate the mass of water (H,O, CHO = 4.181 J g-l °C-) at 20.0°C that would be requireć to cool a 30.0-g block of copper (Cu, co=0.385 Jg-l °C-1) from 50.0°C to 25.0°C in an insulated cup. %3D %3D 10

Calculate the mass of water (H,O, CHO = 4.181 J g-l °C-) at 20.0°C that would be requireć to cool a 30.0-g block of copper (Cu, co=0.385 Jg-l °C-1) from 50.0°C to 25.0°C in an insulated cup. %3D %3D 10

Principles of Modern Chemistry

8th Edition

ISBN:9781305079113

Author:David W. Oxtoby, H. Pat Gillis, Laurie J. Butler

Publisher:David W. Oxtoby, H. Pat Gillis, Laurie J. Butler

Chapter12: Thermodynamic Processes And Thermochemistry

Section: Chapter Questions

Problem 71AP

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