If the specific heat of iron is 0.449 J/g·K, what is the enthalpy change of this process for 100 g of Fe (s)? Is the process end

Question

Stella [2.4K]

2 years ago

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If the specific heat of iron is 0.449 J/g·K, what is the enthalpy change of this process for 100 g of Fe (s)? Is the process end

othermic or exothermic? Explain.

Chemistry

1 answer:

katrin2010 [14] · Answer 1 · 2022-07-13T11:29:03+03:00

Full Question:

Although it is not really a chemical reaction, one could consider a cooling process to be analogous to the enthalpy change that occurs in a reaction. Consider the transformation

Fe (s, T = 300 K) → Fe (s, T = 250 K)

If the specific heat of iron is 0.449 J/g·K, what is the enthalpy change of this process for 100 g of Fe (s)? Is the process endothermic or exothermic? Explain.

Answer:

ΔH = - 2245J

Explanation:

Specific heat capacity, Cp = 0.449 J/g·K

ΔH=MCpΔT

ΔT = 250K - 300K = - 50K

ΔH = 100 * 0.449 * (-50)

ΔH = - 2245J

The iron will lose (give off) heat energy to cool down. Hence, it is an exothermic process. The negative sign of the enthalpy confirms this.