A50.0 g sample of scandium, sc, is heated by exposure to 1.50 x 10 3 j. the temperature of the sc is raised by 61.1 o c. what is the specific heat of sc in j/g· o c?

Given mass of Scandium = 50.0 g

Increase in temperature of the metal when heated =

Heat absorbed by Scandium =

The equation showing the relationship between heat, mass, specific heat and temperature change:

Where Q is heat =

m is mass = 50.0 g

ΔT =

On plugging in the values and solving for C(specific heat) we get,

=50.0g(C)()

C = 0.491

Specific heat of the metal = 0.491

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

c

explanation: