The Dissolution of Barium Hydroxide in Water Is an Exothermic

question 17

Multiple Choice

The dissolution of barium hydroxide in water is an exothermic process. Which statement is correct?

• A) The enthalpy of solid barium hydroxide plus pure water is less than that of the solution, at the same temperature.
• B) The enthalpy of solid barium hydroxide plus pure water is greater than that of the solution, at the same temperature.
• C) The enthalpy of solid barium hydroxide plus pure water is the same as that of the solution, at the same temperature.
• D) The temperature of the solution is lower than of the barium hydroxide and water before mixing.
• E) When barium hydroxide dissolves in water, the system does work on the surroundings.

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Definitions:

Oxygen

Oxygen, a diatomic gas with the molecular formula O2, is critical for respiration in living organisms and supports combustion.

Ionic Compound

A chemical compound formed by the transfer of electrons from one atom to another, resulting in the formation of positively and negatively charged ions.

Aluminum

Aluminum is a lightweight, silver-white metallic element (Al) used extensively in alloys and for its properties of corrosion resistance and high conductivity.

Chlorine

A highly reactive, greenish-yellow gaseous halogen with the symbol Cl and atomic number 17, widely used in water treatment, bleaches, and industrial processes.