DE Unit 9 Quizizz: Buffers

Buffer is defined as

• ability to resist pH change
• ability to prevent pH from decreasing
• ability to resist a pH increase
• ability to resist pH change when small amount of acid added

Acidic buffer is made up of

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

Which of the following combinations is not suitable for making a buffer?

• HClO₄ and NaClO₄

• H₂CO₃ and NaHCO₃

• NH₄Cl and NH₃

• H₃PO₄ and NaH₂PO₄

In a buffer solution of HF and NaF, which would neutralize the addition of a small quantity of HCl?

• F^-

• HF

• OH^-

• H⁺

What is the pH of a buffer that is 0.08 M NaA and 0.1 HA. The Ka of HA = 1.0 x 10^-4.

• 2.16

• 3.90

• 4.00

• 4.10

What is the pH of the solution if 0.089 g of sodium fluoride is added to 135.0 mL of a 0.077 M HF solution? K_a for HF is 6.8 × 10^–4.

• 2.49

• 5.90

• 2.13

• 4.98

What is the pH of a buffer made by combining 181 mL of 0.34 M NaC₂H₃O₂ with 170 mL of 0.28 M HC₂H₃O₂? The K_a of acetic acid is 1.75 × 10^-5.

• 4.88

• 4.64

• 5.93

• 4.81

How many grams of sodium formate (NaCHO₂) must be added to 100 mL to create a buffer with 0.200 M formic acid (HCHO₂) to make a solution with pH = 3.55. K_a for formic acid is 1.7x10^-4

• 0.82 grams

• 0.22 grams

• 0.60 gram

• 12.1 grams

The buffer solution is able to maintain pH by some events, except . . .

• The addition of a little acid

• The addition of a little base

• Dilution

• Addition of water

• The addition of excess acid

Which of the following statements ARE TRUE about buffer solution?

(you may choose more than one answer)

• pH of buffer solution will never change despite addition of small amount of base or acid

• Buffer can be made by mixing weak acid and salt of its conjugate base or by mixing weak base with salt of its conjugate acid

• Buffer has acid and base components that can work specifically to resist pH change

• the closer the ratio of concentration weak acid/base to the concentration of salt of its conjugate base/acid, the less effective the buffer to resist pH change