Bio 264: 2.3 Acids, Bases, pH, and Buffers
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 and 2 1 and 4 1, 3, and 4 2 and 4 2 and 3
2 and 4
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 ions4. A decrease in pH5. An increase in pH 1 and 5 2, 3, and 4 1, 3, and 5 3 and 4 2 and 4
2, 3, and 4
Normal blood pH is maintained within a range of . 3.5-8.5 7.35-7.45 4.5-5.5 1.0-14.0 6.5-9.5
7.35-7.45
How would you describe the solution with a concentration of H+ ions = 1x10-4 M? Basic Acidic Neutral Can't be determined
Acidic
If one were to add a strong acid like H C l to an aqueous solution, which of the following would result? H + would be released into solution The pH would increase The pH would decrease Both H + would be released into solution and the pH would increase Both H + would be released into solution and the pH would decrease
Both H + would be released into solution and the pH would decrease
In the reversible reaction, C O 2 + H 2 O ↔ H 2 C O 3 ↔ H + + H C O 3 − − , a decrease in respiration rate will increase the concentration of C O 2 in the blood. What will this do to the amount of H + in the blood? H + will increase H + will decrease H + will be unchanged
H + will increase
If orange juice has a p H of 4 and a solution of ammonia has a p H of 10, then which of the following answers are true? The H + concentration of orange juice is 4%. Orange juice is an acidic solution. Ammonia is an acidic solution. Orange juice contains fewer H + ions dissolved in an aqueous solution than ammonia.
Orange juice is an acidic solution.
If an acid is added to a buffer, what will happen? Conjugate acid releases H+ Conjugate base releases OH- The additional H+ is bound by the conjugate base preventing a large change in pH 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
Which of the following is true when comparing solutions with a pH of 6 and a pH of 8? 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. 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. 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. 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. 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 a concentration of hydrogen ions that is 100 times lower than a solution with a pH of 6.
Imagine that a solution with a pH = 4 is added to a neutral solution containing the following buffer system: H2CO3 = HCO3- + H+ What would be true after equilibrium is reached? The resultant solution would have a pH of 4. There would be an increased concentration of H2CO3 in the resultant solution. There would be a greater concentration of HCO3- ions dissolved in the resultant solution. The resultant solution would maintain the same number of H+ and HCO3- ions but the pH would change.
There would be an increased concentration of H2CO3 in the resultant solution.
A patient's blood pH changes from 7.4 to 6.90. Which of the following is true? This patient is in a state of alkalosis. This patient is in a state of acidosis. The patient is still within the normal blood pH range.
This patient is in a state of acidosis.
If we say that pure water has a neutral pH, then which of the following [H+] is considered to be acidic? [H+] of 1x10-11 [H+] of 1x10-8 [H+] of 1x10-5 [H+] of 1x10-7
[H+] of 1x10-5
On the pH scale, . a low number corresponds to a strong base a low number corresponds to a high concentration of free hydrogen ions a low number corresponds to a low concentration of free hydrogen ions a low number corresponds to a 100-fold change from water
a low number corresponds to a high concentration of free hydrogen ions
If the [H +] of a solution is less than 1 x 10-7 it is . acidic basic neutral
basic
An increase in blood CO2 . increases blood hydrogen ion concentration and blood alkalinity increases blood hydrogen ion concentration and blood acidity decreases blood hydrogen ion concentration and blood alkalinity decreases blood hydrogen ion concentration and blood acidity
increases blood hydrogen ion concentration and blood acidity
An acid . is a proton acceptor is any substance that binds to H +H + is a molecule or compound that releases H +H + is always completely dissociated in water
is a molecule or compound that releases H +H +
A base . is a proton donor is a proton acceptor is a molecule or compound that releases H +H + is always completely dissociated in water
is a proton acceptor
A conjugate acid-base pair . acts as a buffer can combine with H +in a solution can release H + to combine with OH- describes carbonic acid ( H 2 C O 3 ) and bicarbonate ions ( H C O 3 − ) is all of the above
is all of the above
A buffer . slows down chemical reactions speeds up chemical reactions increases the pH of a solution maintains a relatively constant pH
maintains a relatively constant pH
A buffer system . is a strong acid and strong base combined together is only used in the chemical laboratory setting to regulate the pH of solutions and has nothing to do with regulating body fluid pH prevents large changes in pH by completely binding any extra H+ in solution is a strong acid and strong base combining AND Assists in regulating body fluid pH regulates the pH of a solution by resisting large changes in pH through conjugate acid-base pairs
regulates the pH of a solution by resisting large changes in pH through conjugate acid-base pairs
