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Calculate the number of kilojoules to warm 125 g of iron from 23.5°c to 78.0°c.

1 Answer

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Answer:

3065.63 J = 3.066 kJ.

Step-by-step explanation:

  • We can calculate the amount of heat (Q) needed to warm Fe using the relation:

Q = m.c.ΔT,

where, Q is the amount of heat needed to warm Fe (Q = ??? J).

m is the mass of Fe (m = 125.0 g).

c is the specific heat capacity of Fe (c = 0.45 J/g.°C).

ΔT is the difference in T (ΔT = final temperature - initial temperature = 78.0°C - 23.5°C = 54.5°C).

∴ Q = m.c.ΔT = (125.0 g)(0.45 J/g.°C)(54.5°C) = 3065.63 J = 3.066 kJ.

User Eric Dahlvang
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