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Thermodynamics: Energy and the First Law. Egg placed in boiling water. Man stands still holding a weight at arm’s length. For this reaction H 2 (g) + (1/2)O 2 (g) → H 2 O(g) ΔH = –286 kJ/mol. is pΔV. positive, negative , zero.
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Eggplaced in boiling water NEXUS/Physics Clicker Questions
Manstands still holding a weight at arm’s length. NEXUS/Physics Clicker Questions
For this reaction H2(g) + (1/2)O2(g)→ H2O(g) ΔH = –286 kJ/mol. is pΔV • positive, • negative, • zero NEXUS/Physics Clicker Questions
For this reaction (occurring in a vessel at STP) H2(g) + (1/2)O2 (g)→ H2O(g) , ΔH = –286 kJ/mol. is the magnitude of the internal energy change (|ΔUint|) • Greater than 286 kJ/mol? • Less than 286 kJ/mol? • Equal to 286 kJ/mol? (Hint: Estimate the value of pΔV) NEXUS/Physics Clicker Questions