AP Chemistry· difficulty 4/5
Use the following data to find ΔH for: 2 C(s) + H₂(g) → C₂H₂(g).
What is ΔH for the formation of C₂H₂(g)?
−226 kJ
+620 kJ
−620 kJ
+226 kJ
Explanation
Reverse (1): +1300. Add 2×(2): −788. Add (3): −286. ΔH = 1300 − 788 − 286 = +226 kJ.
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