Concept explainers
Use standard enthalpies of formation in Appendix L to calculate enthalpy changes for the following:
(a) 0.054 g of sulfur burns, forming SO2(g)
(b) 0.20 mol of HgO(s) decomposes to Hg(ℓ) and O2(g)
(c) 2.40 g of NH3(g) is formed from N2(g) and excess H2(g)
(d) 1.05 × 10–2 mol of carbon is oxidized to CO2(g)
(a)
Interpretation:
The enthalpy change for the formation the following reaction has to be determined.
Concept Introduction:
If a reaction proceeds in two or more other reaction,
The change in enthalpy,
Answer to Problem 58PS
The enthalpy change for the formation is
Explanation of Solution
Given mass is
The enthalpy of formation is
The change in enthalpy,
So, the enthalpy change for the formation is
(b)
Interpretation:
The enthalpy change for the formation the following reaction has to be determined.
Concept Introduction:
If a reaction proceeds in two or more other reaction,
Answer to Problem 58PS
The enthalpy change for the formation is
Explanation of Solution
Given mass is
The enthalpy of formation is
The change in enthalpy,
So, the change in enthalpy is
(c)
Interpretation:
The enthalpy change for the formation the following reaction has to be determined.
Concept Introduction:
If a reaction proceeds in two or more other reaction,
Answer to Problem 58PS
The change in enthalpy is
Explanation of Solution
Given mass is
The enthalpy of formation is
The change in enthalpy,
Energy change =
So, the change in enthalpy is
(d)
Interpretation:
The enthalpy change for the formation the following reaction has to be determined.
Concept Introduction:
If a reaction proceeds in two or more other reaction,
Answer to Problem 58PS
The change in enthalpy is
Explanation of Solution
Given mass is
The enthalpy of formation is
The change in enthalpy,
Energy change =
So, the change in enthalpy is
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Chapter 5 Solutions
CHEMISTY+CHEMICAL REACTIVITY
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