A Buffer Is Composed of 0

question 51

Multiple Choice

A buffer is composed of 0.400 mol H₂PO₄^- and 0.400 mol HPO₄^2- diluted with water to a volume of 1.00 L.The pH of the buffer is 7.210.How many moles of HCl must be added to decrease the pH to 6.210?

• A) 0.200 mol
• B) 0.327 mol
• C) 0.360 mol
• D) 0.400 mol
• E) 3.60 mol

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Definitions:

Systematic Desensitization

A behavioral therapy technique used to reduce phobic responses or anxiety by gradual exposure to the feared object or situation in conjunction with relaxation exercises.

Phobias

Intense, irrational fears of specific objects or situations that significantly affect a person's life.

Progressive Relaxation

A technique involving the tightening and then slowly relaxing of different muscle groups to achieve mental and physical relaxation.

Behavior Therapies

Psychological treatments that focus on changing undesirable behaviors through conditioning and reinforcement.