The pressure during the molar heat of fusion is kept________________?
Correct answer: B. one atmosphere
- A. 0 atmosphere
- B. one atmosphere
- C. 2 atmosphere
- D. 10 atmosphere
Explanation
Molar heat of fusion is conventionally measured at constant atmospheric pressure, so the pressure is 1 atmosphere. Students may choose 0 atmosphere by confusing atmospheric pressure with a vacuum, but phase-change enthalpies are commonly specified at 1 atmosphere.
Report an error
The more specific you are, the faster it gets fixed. A source beats an opinion.
Prefer email? [email protected]
About Enthalpy
Enthalpy is the heat content of a system measured at constant pressure, and its change indicates whether a reaction or physical process is endothermic or exothermic. The topic covers state functions, enthalpy diagrams, standard enthalpy of formation, combustion and neutralisation, and the relationship between ΔH and internal energy change.
Practise Thermochemistry and Energetics of Chemical Reactions
728 free Thermochemistry and Energetics of Chemical Reactions MCQs from Chemistry, each with the correct answer and an explanation. Unlimited attempts, no account needed.
Discussion
Stuck on an option, or know a faster way to get there? Ask or explain it here.
No comments yet. Be the first to explain this one.
Exams that ask Chemistry questions like this
Chemistry is on 14 papers prepared for on TestUstad, and all of them draw the same bank, so this question is worth knowing for every one of them.
More Enthalpy questions
All the enthalpy changes are________________?
If a physical and chemical change takes place at a constant pressure then the heat change during the process is called__________________?
The standard enthalpy of combustion is the enthalpy change when
Enthalpy of combustion for food fuel and other compounds can be measured accurately by________________?
Enthalpy of a reaction can be measured by ____________________?
Two rocket fuels below are determined by their high performance.N2H4(l) + O2(g) -> N2(g) + 2H2O(l) ΔH= -632 kJH2 (g) + ½ O2(g) -> H2O(l) ΔH = -286 kJIf equal masses of hydrazine and hydrogen are used, which of the following has better performance?