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Question:

what assumptions can be made?

110 grams of boiling water (temperature 100° C, heat capacity 4.2 J/gram/K) are poured into an aluminum pan whose mass is 900 grams and initial temperature 22° C (the heat capacity of aluminum is 0.9 J/gram/K).Tf 50.330What simplifying assumptions did you have to make?The thermal energy of the aluminum doesn't change.The thermal energy of the water doesn't change.Energy transfer between the system (water plus pan) and the surroundings was negligible during this time.The heat capacities for both water and aluminum hardly change with temperature in this temperature range.

Answer:

nothing can replace an aluminum foil cap on my head to reflect back the aliens thought waveswhich mind control you simple minded half alien and half Bigfoot people who or controlled them.signed Mr Sky Forest Yeti .p.syou may wish to use a foil cap yourself.a whole new world will open to you without there influence in your mind.
scrap metal off an alien space shipDoesn't burn like regular aluminum foil.
For cooking try some parchment paperYou can wrap the food up and it will cook insideIt won't get as hot as foil but it will cook.
Nothing can replace aluminum foil better go buy more keep a extra roll on hand like me
The thermal energy of the aluminum DOES changeIt goes from 22 C to 50.33 CThis in an increase of about 23 kJLikewise the thermal energy of the water DOES changeIt goes from 100 C down to 50.33 CThis is a loss of about 23 kJ You have to assume that heat capacities are temperature independent (they do not change over the range of temperatures in this questions)A very reasonable assumptionYou have to assume that no heat is lost from the water or the pan and no heat is lost in pouring the water into the panYou are assuming that none of the water is leaving the system as steam (not a very good assumption, but if you work fast you can minimize the heat lost to steam) You are assuming the water and pan are in thermal equilibrium - the heat is spread evenly through the water and through the pan so that everything has the same temperature Finally, you have to assume that your instructor has some way to measure these temperaturesMeasuring the temperature of something is very difficult without adding or subtracting energy from the systemThis is not really an assumption that you have to make to work the problemHowever, it would be extremely difficult to experimentally verify this problem Hope this helps.

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