IONIC EQUILIBRIUM & BUFFERS

Question 1

formation of ions

Answer 1

ionization

Question 2

separation of a species into to two or more

Answer 2

dissociation

Question 3

The equilibrium established between the unionized molecules and the ions in the solution of weak electrolytes.

Answer 3

ionic equilibrium

Question 4

degree of ionization is pH dependent

Answer 4

weak electrolytes

Question 5

particles have no charge

Answer 5

unionized

Question 6

with charge

Answer 6

ionized

Question 7

Acid + acid

Answer 7

unionized, lipophilic, insoluble

Question 8

Base + base

Answer 8

unionized, lipophilic, insoluble

Question 9

Acid + base

Answer 9

salt form, ionized, hydrophilic, soluble

Question 10

Formed by a chemical reaction between: a base and an acid.

Answer 10

salts

Question 11

will not completely dissolved in water; they only partially dissolved in water

Answer 11

weak acid & base

Question 12

Protolysis or the transfer of protons

Answer 12

Protolytic Reaction

Question 13

A basic solvent capable of accepting protons from the solute

e.g., acetone, ether, liquid ammonia

Answer 13

protophilic

Question 14

A proton-donating compound and is represented by acids

formic acid, acetic acid, sulfuric acid, liquid HCl, and liquid HF

Answer 14

protogenic

Question 15

Neither accept nor donates protons

hydrocarbons

Answer 15

aprotic

Question 16

A specie that can function either as an acid or base and are said to be amphoteric in nature

Answer 16

ampholyte

Question 17

Compounds or mixtures of compounds that by their presence in a solution, resist changes in pH upon the addition of small quantities of acid or alkali

Answer 17

buffers

Question 18

acetic acid and sodium acetate

Answer 18

weak acid & conj base

Question 19

ammonium hydroxide and ammonium chloride

Answer 19

weak base & conj acid

Question 20

resistance to a change in pH

Answer 20

buffer action

Question 21

acidity constant

Answer 21

Ka

Question 22

basicity constant

Answer 22

Kb

Question 23

self-ionization of water

Answer 23

Autoprotolysis

Question 24

acts both as an acid and as a base

Answer 24

amphoteric

Question 25

water dissociation constant

Answer 25

Kw

Question 26

donates/accepts **one** proton (one Ka)

Answer 26

monoprotic

Question 27

donates/accepts **two or more** protons

Answer 27

polyprotic

Question 28

The **degree of acidity** and **basicity** depends on H+, OH-, pH or pOH

Answer 28

pH value

Question 29

**negative logarithm** of a value

Answer 29

p function

Question 30

pH and pOH lie between

Answer 30

0 - 14

Question 31

The ____ in the scientific notation gives you an **idea** of the pH, and vice versa.

Answer 31

exponential term pH = 8 | [H+] = 1 x 10-⁸

Question 32

the **higher** the **OH-**, the more ____ the substance is

Answer 32

basic

Question 33

the **higher** the **H+**, the more ____ the substance is

Answer 33

acidic

Question 34

strong **acid**

Answer 34

pH = -logCa

Question 35

strong **base**

Answer 35

pH = 14 + logCb

Question 36

weak **acid**

Answer 36

pH = -1/2log(Ca x Ka)

Question 37

weak **base**

Answer 37

pH = 14 + 1/2log(Cb x Kb)

Question 38

The **magnitude** of resistance of buffer to pH changes

Answer 38

Buffer Capacity (β)

Question 39

Buffer Capacity (β) is also known as

Answer 39

Buffer **index** Buffer **efficiency** Buffer **value**

Question 40

Exact Equation for **Buffer Capacity**

Answer 40

B = 2.3C (Ka[H+] / (Ka + [H+])² | C = total conc. of buffer

Question 41

**Maximum** Buffer Capacity

Answer 41

0.576C

Question 42

# **BLOOD** maintained at pH ____

Answer 42

7.4

Question 43

primary buffer in **plasma**

Answer 43

BLOOD

Question 44

# **BLOOD** **secondary** buffer in

Answer 44

erythrocytes

Question 45

# **BLOOD** life threatening at pH

Answer 45

less than 6.9, greater than 7.8

Question 46

# **LACRIMAL FLUID (TEARS)** maintained at pH

Answer 46

7.4

Question 47

# **LACRIMAL FLUID (TEARS)** **discomfort** & **flow** of tears at pH

Answer 47

less than 6.6, greater than 9

Question 48

average pH of **urine**

Answer 48

6 (about 4.5 - 7.8)

Question 49

Frequently used in formulation of **ophthalmic solutions**

Answer 49

pharmaceutical buffers

Question 50

Boric acid + sodium **carbonate** (pH 5-9)

Answer 50

GIFFORD

Question 51

Salts of sodium phosphate + NaCl (pH 6-8)

Answer 51

SORENSEN

Question 52

Salts of sodium phosphate + NaCl (pH 6-8) is also called

Answer 52

PHOSPHATE BUFFERED SALINE (PBS)

Question 53

Boric acid + sodium **borate** + NaCl (pH 7-9)

Answer 53

PALITZSCH

Question 54

# **CLARK-LUBS MIXTURES** HCl & KCl

Answer 54

1.2 - 2.2

Question 55

# **CLARK-LUBS MIXTURES** HCl & potassium hydrogen phthalate

Answer 55

2.2 - 4.0

Question 56

# **CLARK-LUBS MIXTURES** NaOH & potassium hydrogen phthalate

Answer 56

4.2 - 5.8

Question 57

# **CLARK-LUBS MIXTURES** NaOH & KH₂PO₄

Answer 57

5.8 - 8.0

Question 58

# **CLARK-LUBS MIXTURES** H₃BO₃, NaOH, & KCl

Answer 58

8 - 10

Question 59

# **General Procedures for Preparing Pharmaceutical Buffer Solutions** Select a **weak acid** having **pKa** approximately ____ to the **desired pH** at which the buffer is used

Answer 59

equal

Question 60

# **General Procedures for Preparing Pharmaceutical Buffer Solutions** Calculate the ____ of salt and weak acid.

Answer 60

molar ratio

Question 61

# **General Procedures for Preparing Pharmaceutical Buffer Solutions** Concentration of **individual** salt and acid of ____ is **sufficient**

Answer 61

0.05 - 0.5M

Question 62

# **General Procedures for Preparing Pharmaceutical Buffer Solutions** Determine the ____ and ____ Adjust if necessary.

Answer 62

pH & β

Question 63

Expressing the **quantities** of the **hydroxide** and **hydrogen ions** into a **logarithmic scale**

Answer 63

SORENSEN'S pH

Question 64

* One of the **most important properties** of a drug * Can be related to o Physiologic and pharmacologic activity o Solubility o Absorption * Predicts which **direction** an acid-base reaction lies and what **extent** the reaction **goes to completion** o Measures the extent on how a weak acid or weak base will undergo ionization or not

Answer 64

Acid dissociation constant Acidity constant Ka