Which statement correctly identifies lithium-bromide's role in absorption systems?

Which statement correctly identifies lithium-bromide's role in absorption systems?

• A. A salt solution
• B. An absorbent
• C. A solution that creates a pressure difference
• D. All of the above

Answer: (D)

Lithium bromide serves as the absorbent in absorption systems. It is a salt that, when dissolved in water, forms a LiBr–water solution that acts as the medium which absorbs water vapor from the evaporator. This absorption releases heat, and the solution’s properties keep the vapor pressure of the refrigerant low in the absorber, helping establish the driving force for movement of vapor from the evaporator to the absorber. Because the cycle relies on a pressure difference to move refrigerant through the system, the LiBr solution contributes to that pressure differential as part of its role as the absorbent. So lithium bromide is effectively a salt solution and the absorbent, and it helps create the needed pressure difference that drives the cycle.

Lithium bromide serves as the absorbent in absorption systems. It is a salt that, when dissolved in water, forms a LiBr–water solution that acts as the medium which absorbs water vapor from the evaporator. This absorption releases heat, and the solution’s properties keep the vapor pressure of the refrigerant low in the absorber, helping establish the driving force for movement of vapor from the evaporator to the absorber. Because the cycle relies on a pressure difference to move refrigerant through the system, the LiBr solution contributes to that pressure differential as part of its role as the absorbent. So lithium bromide is effectively a salt solution and the absorbent, and it helps create the needed pressure difference that drives the cycle.