Acids and Bases Flashcards Preview

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Flashcards in Acids and Bases Deck (19):
0

What is litmus paper?

It is a chemical indicator that turns red in acidic solutions and blue in basic solutions. It changes color as the comprised chemicals dissociate. Indicators signal the end point during titration.

1

Who described bases as hydroxide ion producers in aqueous solutions?

Svante Arrhenius also defined acids as proton producers in aqueous solutions.

2

How do Johannes Brønsted and Thomas Lowry define acids and bases?

The Brønsted-Lowry definition describes acids as proton donors and bases as proton acceptors.

3

Conjugate Acids and Bases

Appearing on opposite sides of the chemical equation, conjugate acids and bases are the protonated/ deprotonated forms of a chemical.

4

What is the most inclusive definition of acids and bases?

The Lewis definition describes acids as electron-pair acceptors and bases as electron-pair donors.

5

pH

pH = -log[H+]

6

pOH

pOH = -log[OH-]

7

Water Dissociation Constant

Kw = [H+][OH-]

At 25°C, Kw = 10^-14 and pKw = 14

8

Acid Dissociation Constant

The degree of acid dissociation, where a weak acid has a smaller Ka.

9

PI

The isoelectric point is where there is no electrical charge.

10

Strong Acid

Acids that completely dissociate in aqueous solutions, like HClO4, HNO3, HI, H2SO4, and HCl.

11

Diprotic Base

Two moles of protons accepted per mole of base.

12

Which reaction between an acid and base form a water and salt?

Neutralization reactions form water and salt. These tend to be between a strong acid and strong base or a weak acid and strong base. Weak bases tend to not be hydroxides.

13

Amphoteric

A chemical that can either be an acid or a base depending on its chemical environment.

14

Titration

A procedure used to determine an unknown concentration of known volume by adding a solution of known concentration and known volume to the point of molar equivalency as shown by an indicator.

15

Half-Equivalence Point

Point of titration when exactly half the molar equivalence of reactant has been consumed by the titration, where the pK equals the pH.

16

Equivalence Point

It occurs when an equimolar amount of titrant has been added.

17

Buffets

Mixture of a weak acid an it's salt that resists changes in pH.

18

Henderson-Hasselbalch Equation

pH = pKa + log ([conjugate base]/[weak acid])

pOH = pKb + log ([conjugate acid]/[weak base])