Thermochemistry questions(1)

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Dhamnekar Winod
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Thermochemistry questions(1)

Post by Dhamnekar Winod »

A 48.59 gram sample of iron (with a heat capacity of 0.450 J/g ºC) is heated to 100.0 ºC. It is then transferred to a coffee cup calorimeter containing 66.51 g of water (specific heat of 4.184 J/ g ºC) initially at 20.63 ºC. If the final temperature of the system is 23.59 ºC, how much heat was absorbed by the calorimeter? Record your answer as a whole number (assume the sign is positive).

I am working on this question. Any chemistry help, hint or correct answer will be accepted.
Last edited by Dhamnekar Winod on Thu Jul 01, 2021 3:30 am, edited 1 time in total.
Any science consists of the following process. 1) See 2)Hear 3)Smell,if needed 4)Taste, if needed 5)Think 6)Understand 7)Inference 8)Take decision [Believe or disbelieve, useful or useless, true or false, cause or effect, any other criteria]
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ChenBeier
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Re: Thermochemistry questions(1)

Post by ChenBeier »

It is not asked. You can calculate the heat what was absorbed by the water.
But you could calculate the Initial temperature of iron.
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Dhamnekar Winod
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Re: Thermochemistry questions(1)

Post by Dhamnekar Winod »

This reaction released 1670.743 J of heat out of which 847.04 Jwas absorbed by coffee-cup calorimeter and 823.70 J was absorbed by water.
Any science consists of the following process. 1) See 2)Hear 3)Smell,if needed 4)Taste, if needed 5)Think 6)Understand 7)Inference 8)Take decision [Believe or disbelieve, useful or useless, true or false, cause or effect, any other criteria]
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Re: Thermochemistry questions(1)

Post by ChenBeier »

The absorbtion of 823,7 kJ/ mol for water is correct. But how you get the other values. What is the 7nitial temperature of iron?
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Dhamnekar Winod
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Re: Thermochemistry questions(1)

Post by Dhamnekar Winod »

Initial temperature of iron was 100.0℃ and its final temperature is equal to final temperature of the system which is 23.59℃. So ∆T for 48.59 g sample of iron is 100.0℃- 23.59℃= 76.41℃.
If you read carefully, you will notice that the questioner asked how much heat absorbed by coffee cup calorimeter, not by water.
Any science consists of the following process. 1) See 2)Hear 3)Smell,if needed 4)Taste, if needed 5)Think 6)Understand 7)Inference 8)Take decision [Believe or disbelieve, useful or useless, true or false, cause or effect, any other criteria]
Orcio_Dojek
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Re: Thermochemistry questions(1)

Post by Orcio_Dojek »

True, but calorimeter constant is unknown.
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