The Solubilities of Ammonium Bromide, NH₄Br, in Water at 0°C

question 47

Multiple Choice

The solubilities of ammonium bromide, NH₄Br, in water at 0°C, 20°C, and 80°C are as follows:
Which of the following fractional crystallization schemes would produce the highest percent yield for the recrystallization of ammonium bromide?

• A) A solution containing 50.5 g NH₄Br in 100.0 g H₂O at 20°C is cooled to 0°C.
• B) A solution containing 115 g NH₄Br in 200 g H₂O at 80°C is cooled to 0°C.
• C) A solution containing 120 g NH₄Br in 100 g H₂O at 80°C is cooled to 20°C.
• D) A solution containing 100 g NH₄Br in 100.0 g H₂O at 80°C is cooled to 20°C.
• E) A solution containing 95 g NH₄Br in 175 g H₂O at 80°C is cooled to 0°C.

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