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Topic: Determining mass of water through heat transfer  (Read 2671 times)

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Offline tickno

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Determining mass of water through heat transfer
« on: October 01, 2010, 12:25:08 AM »
hey guys i just got a homework question and revision for exam.
i need a bit of help :(

A 40.08 g bar of aluminium (which has a molar heat capacity of 24.03 J mol -1 K -1) is heated to 66.77 ºC and dropped into a calorimeter containing water (with a specific heat capacity of 4.180 J g -1 K -1) initially at 22.46 ºC. The final temperature of the water is 41.53 ºC. Calculate the mass of water (in g) in the calorimeter.


Atomic weight Al= 26.98 g mol -1



anyone know how to do this?

Offline sjb

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Re: Determining mass of water through heat transfer
« Reply #1 on: October 01, 2010, 02:25:37 AM »
hey guys i just got a homework question and revision for exam.
i need a bit of help :(

A 40.08 g bar of aluminium (which has a molar heat capacity of 24.03 J mol -1 K -1) is heated to 66.77 ºC and dropped into a calorimeter containing water (with a specific heat capacity of 4.180 J g -1 K -1) initially at 22.46 ºC. The final temperature of the water is 41.53 ºC. Calculate the mass of water (in g) in the calorimeter.


Atomic weight Al= 26.98 g mol -1



anyone know how to do this?

How much heat energy did the bar of aluminium lose? So how much did the water gain?

Offline tickno

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Re: Determining mass of water through heat transfer
« Reply #2 on: October 01, 2010, 07:35:43 AM »
well thats the thing.

you use q=mc delta t ...right?
 
but like whats change in T.

it says it was heated to that temperature....but it doesnt say what from....or am i looking at 66.77 down to 41.53? for the aluminium.

and 22.46 to 41.53 for the water?

Offline Borek

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Re: Determining mass of water through heat transfer
« Reply #3 on: October 01, 2010, 12:27:47 PM »
66.77 down to 41.53? for the aluminium.

and 22.46 to 41.53 for the water?

Yes.
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