BMS481_2.0

Buffer is defined as

• ability to change a pH

• ability to prevent pH from decreasing

• ability to resist a pH increase

• minimizes the changes in the concentrations of H⁺ and OH^-

Why do cells need a buffer system?

• Chemical processes in the cell are sensitive to the concentration of H⁺ and OH^-

• Cells do not have a buffer system

• Cells need acids and bases to survive

• The pH range of cells can withstand large changes

If some process releases acid [H⁺] into the blood, this equilibrium responds by shifting to the left as long as there is HCO₃^-present for the H⁺ to react with, thus removing the excess H⁺ions. What happens after the release of H⁺?

• pH never lowers

• pH is lowered and then immediately restored

• pH raises and then is restored

• ph lowers and remains low

Tags

NGSS.HS-LS1-3

Why were the biological samples generally good buffers?

• Water is a poor buffer

• They need to maintain a pH of 8.0 at all times

• All living organisms need to maintain homeostasis in terms of pH

• The samples came in liquid form

Tags

NGSS.HS-LS1-3

Which type of titration is shown by this titration curve?

• Titration of a strong acid by a strong base 
• Titration of a weak acid by a strong base 
• Titration of a strong base by a strong acid 
• Titration of a weak base by a strong acid

The pH at the equivalence point of the titration of a strong acid with a strong base is usually:

• acidic 3.9
• acidic 4.5
• neutral 7.0
• basic 8.2

Basic buffer is made up of

• weak base and weak acid
• weak base and its conjugate salt
• weak base and its conjugate acid
• strong base and its conjugate acid

Which mixtures act as buffer solutions?

• I and II
• I and III
• II and III
• I, II and III

Suppose you have a solution of 0.3 M HBrO and 0.3 M BrO. You add a small amount of NaOH to this buffer solution. What is the reaction that takes place?

• H⁺ + BrO^- --> HBrO
• OH^- + H⁺ --> H₂O
• OH^- + HBrO --> H₂O + BrO^-
• OH^- + BrO^- --> O^-2 + HBrO

which would be an overall explanation for how a buffer works

• The mixture of ions and molecules in a buffer solution resists changes in pH by reacting with any hydrogen ions or hydroxide ions added to the buffer solution

• The conjugate base ions in the buffer solution resists changes in pH by reacting with any hydroxide ions added to the buffer solution

• The undissociated acid molecules in the buffer solution resists changes in pH by reacting with any acid H⁺ ions added to the buffer solution

• None of the above