Comprehension Check: Acids and Bases
Comprehension Check
1. pH is a scale used to determine how many Hydroxide ions are in a solution
a. True
b. False
2. Lemon Juice has a pH of 3. What does this make it?
a. Basic
b. Acidic
c. Neutral
d. None of the above
3. What are pH strips used for, and why do they work?
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4. Which definition of acids and bases does NOT exist?
a. Arrhenius Definition
b. Lewis Definition
c. Proton Definition
d. Bronsted-Lowry Definition
5. What is the difference between a strong acid/base and a weak acid/base?
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6. What does dissociate mean?
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7. Given the chemical equation:
Chemical Equation
What are the conjugate pairs?
8. When an acid and base mix, they cancel each other out and produce water and a salt
a. True
b. False
9. Give an example when Titration could be useful
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10. What is equivalence point?
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Answers
1. False, pH is used to determine how many Hydrogen ions are in solution. The equation can be reworked to represent Hydroxide ions, however, so don’t get it confused!
2. Acidic. Anything below a pH of 7 is acidic. Above 7 is basic, and 7 is neutral.
3. pH strips are used to determine the pH of a solution. They are usually coated in a universal indicator which changes color when you dip it into the solution. You can then compare the color to a predetermined chart to figure out the pH
4. Proton definition is not a definition for acids and bases. Definitely look into the other three though, they are important to know!
5. A strong acid/base completely dissociates in water. A weak acid/base still dissociates, but not entirely.
6. Dissociate means to break apart.
7.
8. True. When an acid and base are perfectly equal, they will cancel each other out in a reaction called neutralization. This process will leave you with some neutral water, and a salt. Not necessarily table salt, but a salt nonetheless.
9. Any example works here as long as the titration process is used to find an unknown concentration of an acid/base using a known concentration of a base/acid.
10. The equivalence point is when the number of moles of an acid exactly equals the number of moles of a base. They balance each other out and reach equivalence.