Methanol (CH3OH) is made industrially in two steps from CO and H2. It is so cheap to make that it is being considered for use as a precursor to hydrocarbon fuels, such as methane (CH4):
Step 1.
Step 2.
- (a) Calculate ΔH° in kilojoules for Step 1.
- (b) Calculate ΔG° in kilojoules for Step 1.
- (c) Is Step 1 spontaneous at 298 K?
- (d) Which term is more important, ΔH° or ΔS°?
- (e) In what temperature range is Step 1 spontaneous?
- (f) Calculate ΔH° for Step 2.
- (g) Calculate ΔG° for Step 2.
- (h) Is Step 2 spontaneous at 298 K?
- (i) Which term is more important, ΔH° or ΔS°?
- (j) In what temperature range is Step 2 spontaneous?
- (k) Calculate an overall ΔG°, ΔH°, and ΔS° for the formation of CH4 from CO and H2.
- (l) Is the overall reaction spontaneous at 298 K?
- (m)If you were designing a production facility, would you plan on carrying out the reactions in separate steps or together? Explain.
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Chapter 8 Solutions
General Chemistry: Atoms First
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