2.3 Acids, Bases, pH, and Buffers

Normal blood pH is maintained within a range of _______. 1) 3.5 - 8.5 2) 7.35 - 7.45 3) 4.5 - 5.5 4) 1.0 - 14.0 5) 6.5 - 9.5

7.35-7.45

In the reversible reaction, CO2 + H2O ↔ H2CO3 ↔ H+ + HCO3-- , a decrease in respiration rate will increase the concentration of CO2 in the blood. What will this do to the amount of H+ in the blood? 1) H+ will increase 2) H+ will decrease 3) H+ will be unchanged

H+ will increase

If an acid is added to a buffer, what will happen? 1) Conjugate acid releases H+ 2) Conjugate base releases OH- 3) The additional H+ is bound by the conjugate base preventing a large change in pH 4) The additional H+ is bound by the conjugate acid preventing a large change in pH

The additional H+ is bound by the conjugate base preventing a large change in pH

Imagine a solution with a pH of 10^-4 that is added to a neutral solution that has an active buffer system that operates via the following reaction. H2CO3 <-- --> HCO3- + H+ What would be TRUE after equilibrium is reached? 1) The resultant mixture would have a pH of 4 2) There would be an increase in the amount of H2CO3 in the resultant mixture 3) There would be a larger number of HCO3- ions dissolved in the resultant solution than there were before the solutions were mixed. 4) Nothing would change. The two mixtures would maintain the same number of H+ and HCO3- ions dissolved in solution but the pH would change

There would be an increase in the amount if H2C03 in the resultant mixture.

A patient's blood chemistry shows a pH change from a normal value of 7.34 to 6.90. Which of the following are TRUE? 1) This patient may be suffering from alkalosis 2) This patient may be suffering from acidosis 3) Neither a nor b is correct. This patient's blood pH is still within normal parameters.

This patient may be suffering from acidosis (drops below 7.35)

If we say that pure water has a neutral pH, then which of the following [H+] is considered to be acidic? 1) [H+] of 1x10^-11 2) [H+] of 1x10^-8 3) [H+] of 1x10^-5 4) [H+] of 1x10^-7

[H+] of 1x10^-5

On the pH scale, 1) a low number corresponds to a strong base 2) a low number corresponds to a high concentration of free hydrogen ions 3) a low number corresponds to a low concentration of free hydrogen ions 4) a low number corresponds to a 100-fold change from water

a low number corresponds to a high concentration of free hydrogen ions

What happens when an acid is added to an aqueous solution? 1. a decrease in [H+] 2. an increase in [H+] 3. dissociation of H+ and other ions 4. a decrease in pH 5. an increase in pH

increase in H+, dissociation of H+ and other ions, a decrease in pH (2,3,4)

An increase in blood CO2 ____________. 1) increases blood hydrogen concentration and blood alkalinity. 2) increases blood hydrogen concentration and blood acidity. 3) decreases blood hydrogen concentration and blood alkalinity. 4) decreases blood hydrogen concentration and blood acidity.

increases blood hydrogen concentration and blood acidity

An acid is... 1) is a proton acceptor 2) is any substance that binds to H+ 3) is a molecule or compound that releases H+ 4) is always completely dissociated in water

is a molecule or compound that releases H+

A base is... 1) is a proton donor 2) is a proton acceptor 3) is a molecule or compound that releases H+ 4) is always completely dissociated in water

is a proton acceptor

A buffer 1) slows down chemical reactions. 2) speeds up chemical reactions. 3) increases the pH of a solution. 4) maintains a relatively constant pH.

maintains a relatively constant pH

If a solution with a concentration of H ions of 10^-4 is added to an equal volume of solution with a concentration of OH ions at 10^-10, what would be the resultant pH after equilibrium was reached? 1) Basic 2) Acidic 3) Neutral 4) Can't be determined

Acidic

If orange juice has a pH of 4 and a solution of Ammonia has a pH of 10, then which of the following answers are TRUE? 1) the H+ concentration of orange juice is 4% 2) Orange Juice is an Acidic Solution 3) Ammonia is an Acidic Solution 4) Orange Juice contains fewer H+ ions dissolved in an aqueous solution than Ammonia

Orange juice is an acidic solution (pH<7)

A buffer system 1) is a strong acid and strong base combined together 2) is only used in the chemical laboratory setting to regulate the pH of solutions and has nothing to do with regulating body fluid pH 3) prevents large changes in pH by completely binding any extra H+ in solution 4) is a strong acid and strong base combining AND Assists in regulating body fluid pH 5) regulates the pH of a solution by resisting large changes in pH through conjugate acid-base pairs

Prevents large changes in pH by acting as a conjugate acid-base pairs AND assists in regulating the body fluid pH

Which of the following statements about a base is true? 1. Adding a base to an aqueous solution would decrease the pH. 2. Adding a base to an aqueous solution would decrease [H+]. 3. There is an increased amount of [H+] in an aqueous solution when a base is added. 4. A base has a pH higher than 7.0. 1) 1, 2 2) 1, 4 3) 1, 3, 4 4) 2, 4 5) 2, 3

adding a base to an aqueous solution would decrease the [H+], a base has a pH higher than 7.0 (2,4)

A conjugate acid-base pair 1) acts as a buffer. 2) can combine with H+ in a solution. 3) can release H+ to combine with OH-. 4) describes carbonic acid (H2CO3) and bicarbonate ions (HCO3-). 5) All of these are correct.

all of these are correct

If the [H+] of a solution is less than 1.0 x 10^-7 it is 1) acidic 2) basic 3) neutral

basic

If one were to add a strong acid like HCl to an aqueous solution, which of the following would result? 1) H+ would be released into solution 2) The pH would increase 3) The pH would decrease 4) Both H+ would be released into solution and the pH would increase 5) Both H+ would be released into solution and the pH would decrease

both H+ would be released into solution and the pH would decrease

Which of the following is TRUE when comparing solutions with a pH of 6 and a pH of 8? 1) The solution with a pH of 8 has a concentration of hydrogen ions that is 100 times higher than a solution with a pH of 6 2) The solution with a pH of 8 has a concentration of hydrogen ions that is 2 times higher than a solution with a pH of 6 3) The solution with a pH of 8 has a concentration of hydrogen ions that is 100 times lower than a solution with a pH of 6 4) The solution with a pH of 8 has a concentration of hydrogen ions that is 2 times lower than a solution with a pH of 6 5) The hydrogen ion concentration does not appreciably differ between a solution with a pH of 8 versus that with a pH of 6.

the solution with a pH of 8 has concentration of hydrogen ions that is 100 times lower than a solution with a pH of 6