An copper mass is heated and placed in a foam cup calorimeter containing 45.0 ml of water at 24.0 degrees celcius. the water reaches a temparture of 75 degrees celcius. how many joules of heat were released by the copper? the density of water is 1g/ml. the specific heat of water is 4.18 j/g degrees

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= 9,593.1 Joules

Explanation:

Heat absorbed by water is equivalent to heat released by copper.

Heat absorbed is given by;

Q = mcΔT

where m is the mass, c is the specific capacity and ΔT is the change in temperature.

Therefore;

Since dnsity of water is 1 g/mL, and specific heat capacity is 4.18 J/g°C while the change in temperature is (75-24) = 51°C.

Heat absorbed by water = 45 g × 4.18 J/g°C × 51

                                         = 9,593.1 Joules

Therefore, the heat released by copper is 9,593.1 Joules

first, consult an activity series chart to determine if al is more reactive than fe. it is, so it will replace the fe. now, one can continue with the problem.

next, make sure you have a correctly balanced equation.

3feo + 2al ==> 3fe + al2o3

now, determine which reactant (feo or al) is in limiting supply.

moles feo present = 125 g x 1 mole/71.8 g = 1.74 moles

moles al present = 25.0 g x 1 mole/26.98 g = 0.927 moles

since from the balanced equation, it take 3 mol feo for every 2 mol al, al will be limiting.

you can determine this simply by dividing moles of each by their coefficient in the balanced equation. for example: 1.74/3 = 0.58 and 0.927/2 = 0.464. al is less, so it is limiting.

finally, using the stoichiometry in the balanced eq. determine mass of fe that can be produced from 0.927 moles of al.

0.927 moles al x 3 moles fe/2 moles al x 55.8 g/mole = 77.6 g

no, the red giant is the hottest with 2.00.000.000 degrees celsius. while the white dwarf only 25,000 degrees celsius.