A 42.5 g piece of aluminum (which has a molar heat capacity of 24.03 j/ocmol) is heated to 82.4oc and dropped into a calorimeter containing water (specific heat capacity of water is 4.18 j/goc) initially at 22.3oc. the final temperature of the water is 24.9oc. calculate the mass of water in the calorimeter. ignore significant figures for this problem.

Question

Physics

Jagger Ford

19 July, 17:31

A 42.5 g piece of aluminum (which has a molar heat capacity of 24.03 j/ocmol) is heated to 82.4oc and dropped into a calorimeter containing water (specific heat capacity of water is 4.18 j/goc) initially at 22.3oc. the final temperature of the water is 24.9oc. calculate the mass of water in the calorimeter. ignore significant figures for this problem.

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Jamya · Answer 1

1. Use the equation q = nC∆T

n = mols of aluminum = 42.5g / 6.98g/mol

C = molar heat capacity = 24.03 j/Cmol

∆T = change in T from what it was before placed in calorimeter to after =

24.9C-82.4C (because water final and metal will be same temp.)

plug in to calculate q of metal =

q = (42.5/6.98) * (24.03J) (24.9-82.4)

q = - 2176.5498 J

qmetal = - q of water

plug in values for water

- (-2176.5498 J) = mC∆T (m = mass of water in grams)

m = q/C∆T

∆T=24.9-22.3 C = 2.6

2176.5498 J / (2.6x4.184) = m = 200.2714 g