Chemistry - Thermochemistry Question with Solution | TestHub
The enthalpy change for the following process would be expected to be a negative for
Options:(select one or more)
Answer:
Solution:
(a) This reaction is the reverse of the ionization of Na, meaning it represents the gain of an electron by a sodium ion. Therefore, the enthalpy change (Δ H) is equal to the negative of the ionization energy (IE), so Δ H = -IE < 0.
(b) This reaction describes the electron gain by fluorine, which is an exothermic process, meaning Δ H < 0.
(c) This reaction involves the formation of an ionic lattice from gaseous ions. The enthalpy change (Δ H) for this process is equal to the negative of the lattice energy (U), so Δ H = -U < 0.
(d) The vaporization of water is an endothermic process, meaning it absorbs heat from the surroundings. Therefore, Δ H > 0.
The correct answers are (a), (b), and (c).
