EXERCISE 6 Flashcards
1
Q
- derived by reacting an OXOACID with a HYDROXYL compound such as an alcohol or phenol
- UBIQUITOUS
- POLAR molecules, but their boiling points are lower than those of carboxylic acids and alcohols of similar molecular weight
- NO intermolecular hydrogen bonding between ester molecules
A
ESTERS
2
Q
ESTERS
derived by reacting an ____ with a ____
A
oxoacid with a hydroxyl compound
3
Q
ESTERS
polar or nonpolar?
A
polar
4
Q
ESTERS
their BOILING POINTS are ____ than those of carboxylic acids and alcohols of similar molecular weight
A
LOWER
5
Q
ESTERS
____ between ester molecules
A
NO intermolecular hydrogen bonding
6
Q
BOILING POINT
ETHYL ACETATE
A
77 C
7
Q
BOILING POINT
PENTANOL
A
138 C
8
Q
BOILING POINT
BUTANOIC ACID
A
164 C
9
Q
ESTER formula
A
RCOOR
10
Q
the process of ester formation happens when a CARBOXYLIC ACID and an ALCOHOL reacts in the presence of an acid catalyst, an ester and water is formed
A
FISCHER ESTERIFICATION
11
Q
FISCHER ESTERIFICATION
ester formation happens when a ____ and an ____ reacts in the presence of an acid catalyst
A
carboxylic acid & alcohol
12
Q
FISCHER ESTERIFICATION
PRODUCT
A
ester and water
13
Q
ESTERS
are usually derived from ____ where the -OH group is replaced by an -O- (alkoxy) group
A
organic acid
14
Q
CARBOXYLIC ACID formula
A
RCOOH
15
Q
ETIOLOGY OF ESTER
- coined in 1848 by German chemist ____
A
LEOPOLD GMELIN
16
Q
ETIOLOGY OF ESTER
coined in ____
A
1848
17
Q
ETIOLOGY OF ESTER
probably as a contraction of the GERMAN ____
A
essigather
(acetic ether)
18
Q
USE OF ESTERS
esters have distinct and characteristic ____ odor
A
fruity-like
19
Q
USE OF ESTERS
most esters are responsible for the odor of ____
A
fruits
20
Q
USE OF ESTERS
ODOR:
____ in PINEAPPLES
A
ethyl ethanoate
21
Q
USE OF ESTERS
ODOR:
____ in APPLES and BANANAS
A
3-methylbutanoate
22
Q
USE OF ESTERS
ODOR:
____ in APPLES
A
3-methylbutyl-3-methylbutanoate
23
Q
USE OF ESTERS
ODOR:
____ in ORANGES
A
octyl ethanoate
24
Q
USE OF ESTERS
____ are used as fragrances, found in essential oils and also on pheromones
A
LMW esters
25
# **USE OF ESTERS**
**LMW esters** are found in ____ and also in ____
essential oils and pheromones
26
# **USE OF ESTERS**
medicines in the market are in the form of esters to ____
enhance its solubility
27
# **USE OF ESTERS**
products that has **poor solubility** so they are marketed in the form of esters
* hydrocortisone sodium succinate
* enalapril maleate
* erythromycin estolate
28
# **USE OF ESTERS**
esters are also commonly used as ____
SOLVENTS
29
# **USE OF ESTERS**
esters as SOLVENTS
ethyl acetate
butyl acetate
30
# **REAGENTS**
* a **dehydrated**/**dehydration** product of **acetic acid** (acetic acid w/o water)
* **colorless** liquid with **STRONG VINEGAR-like** odor
* **hydrolyzed** into **two acetic acid** molecules upon reaction with the **moisture** in **air**
* the **hydroxyl (-OH)** group of **acetic acid** is replaced wtih **alkoxy (-O-alkyl)** group upon reaction with an **alcohol**
ACETIC ANHYDRIDE
31
# **REAGENTS | ACETIC ANHYDRIDE**
SYNONYM
ethanoic anhydride
32
# **REAGENTS | ACETIC ANHYDRIDE**
hydrolyzed into ____ upon reaction with the **moisture in air**
two acetic acid molecules
33
# **REAGENTS | ACETIC ANHYDRIDE**
the **hydroxyl (-OH)** group of acetic acid is **replaced** with ____ group upon reaction with an **alcohol**
alkoxy (-O-alkyl)
34
# **REAGENTS**
* highly **CORROSIVE** colorless liquid
* used as **CATALYST** to **accelerate** the **reaction** of **acetic acid** with the **alcohol**
CONC. SULFURIC ACID
35
# **REAGENTS**
* colorless solution with **STRONG ODOR**
* primarily used as **SOLVENTS**
* are the **source** of the **alkoxy** group
ALCOHOLS
36
# **REAGENTS**
used to **hydrolyze** any **EXCESS UNREACTED acetic anhydride** into acetic acid
DISTILLED WATER
37
# **REAGENTS**
* **pulls the water** from the organic layer to the aqueous layer because **salts** have a **stronger attraction** to **water** than to **organic solvents**
SODIUM CHLORIDE SOLUTION
38
# **REAGENTS**
aids in the **separation** of **LAYER** during ester synthesis
saturated NaCl
39
# **REAGENTS**
* **NaHCO₃**
* the **crude ester** in the **organic layer** contains some **unreacted acetic anhydride**
* it is **removed** by **washing** with ____
SODIUM BICARBONATE SOLN
40
# **REAGENTS**
* Na₂SO₄
* used to **dehydrate** the **organic layer** by **ABSORBING any WATER** molecules present in it
ANHYDROUS SODIUM SULFATE
41
# **SYNTHESIS**
____, ____, ____ was mixed in an Erlenmeyer flask
acetic anhydride
sulfuric acid
alcohol
42
# **SYNTHESIS**
the **alcohol** must be added ____ **while swirling** to ensure complete reaction
dropwise
43
# **SYNTHESIS**
mixture was ____ to **induce reaction**
heated
44
# **SYNTHESIS**
____ was added to **hydrolyze** excess acetic anhydride
water
45
* the formation of esters takes **TOO LONG** to proceed
* the equilibrium **does not** favor the formation of the ester
* therefore the equilibrium must be **SHIFTED TO RIGHT** in favor of the product
* one approach is to use an **EXCESS** of one of the reactants
* **acetic anhydride** yields two moles of **acetic acid** upon **hydrolysis**
LE CHATELIER'S PRINCIPLE
46
* it is an observation on **CHEMICAL EQUILBRIA** of reactions
* it covers **changes** to the **position** of **equilibrium** if there is a change on the concentration, pressure or temperature
* if a **dynamic equilibrium** is distributed by changing the conditions, the position of the equilibrium moves to counteract the change
LE CHATELIER'S PRINCIPLE
47
# **EXTRACTION**
____ is added to **remove EXCESS WATER**
half saturated sodium chloride
48
# **EXTRACTION**
the solution is shaken in a ____
separatory funnel
49
# **EXTRACTION**
what layer is **DISCARDED**
LOWER layer
50
# **EXTRACTION**
____ was added to **remove excess ACETIC ANHYDRIDE**
saturated sodium bicarbonate
51
# **EXTRACTION**
**THIRD** extraction was done using a ____
saturated sodium chloride
52
# **DRYING AND FILTRATION**
____ is placed on a **filter paper**
anhydrous sodium sulfate
53
# **PHYSICAL TEST**
ODOR
no vinegar-like odor
54
* employed to ddetermine if esters were formed by the virtue that these compounds are **hydrolyzed** into **acid** and **alcohol**
* are **ONE WAY reactions** (**IRREVERSIBILE**) and the products are **easier** to **separate**
* the ester formed was **hydrolyzed** by **heating** it with a **dilute alkali** (**sodium hydroxide**)
* then a **strong acid** (**sulfuric acid**) was added
* the protons in the acid reacts with acetate ion, producing **acetic acid** (presence is identied by the **vinegar-like odor**)
BASE HYDROLYSIS OF ESTERS
55
# **BASE HYDROLYSIS OF ESTERS**
employed to determine if **esters** were **formed** by the **virtue** that these compounds are **hydrolyzed** into ____ and ____
acid and alcohol
56
# **BASE HYDROLYSIS OF ESTERS**
are ____ reactions and the products are **easier** to **separate**
ONE WAY
(**irreversible**)
57
# **BASE HYDROLYSIS OF ESTERS**
the ester formed was **hydrolyzed** by **HEATING** it with a ____
dilute **alkali**
(**sodium hydroxide**, NaOH)
58
# **BASE HYDROLYSIS OF ESTERS**
the **protons** in the **acid** reacts with **acetate ion**, producing ____
| presence is identified by the vinegar-like odor
acetic acid
59
# **BASE HYDROLYSIS OF ESTERS**
a **STRONG ACID** that was added
sulfuric acid
60
# **ESTER PRODUCTS**
ACETIC ACID + **ETHYL** ALCOHOL
ethyl acetate
61
# **ESTER PRODUCTS**
* found in **CEREAL crops**, **RADISHES**, **FRUIT JUICES**
* FORMULA: **C₄H₈O₂**
* ODOR: **fruity** odor
* USES:
* **artificial fruit essence**
* **solvent**
* **used in printing and marking**
EHTYL ACETATE
62
# **ESTER PRODUCTS**
ETHYL ACETATE:
formula
C4H8O2
63
# **ESTER PRODUCTS**
ACETIC ACID + **ISOPROPYL** ALCOHOL
isopropyl acetate
64
# **ESTER PRODUCTS**
* found in **ALCOHOLIC beverages**, **MELONS**, **APPLES**, **BANANAS**
* FORMULA: **C₅H₁₀O₂**
* ODOR: **fruity** odor
* USES:
* **solvent for CELLULOSE**
* **component of PRINTING INKS and PERFUMES**
ISOPROPYL ACETATE
65
# **ESTER PRODUCTS**
ACETIC ACID + **ISOPENTYL** ALCOHOL
ISOPENTYL ACETATE
66
# **ESTER PRODUCTS**
* found in **APPLE** and **BANANA**
* FORMULA: **C₇H₁₄O₂**
* ODOR: **BANANA-like**
* USES: **banana flavoring**
ISOPENTYL ACETATE
67
# **ESTER PRODUCTS**
ISOPROPYL ACETATE:
formula
C5H10O2
68
# **ESTER PRODUCTS**
ISOPENTYL ACETATE:
formula
C7H14O2
69
# **ESTER PRODUCTS**
ACETIC ACID + **PROPYL** ALCOHOL
PROPYL ACETATE
70
# **ESTER PRODUCTS**
* found in **APPLE** and **PEAR**
* FORMULA: **C₅H₁₀O₂**
* ODOR: **PEAR-like**
* USES:
* **flavoring agent**
* **solvent**
PROPYL ACETATE
71
# **ESTER PRODUCTS**
PROPYL ACETATE:
formula
C5H10O2
72
# **ESTER PRODUCTS**
ACETIC ACID + **BENZYL** ALCOHOL
BENZYL ACETATE
73
# **ESTER PRODUCTS**
* found in **JASMINE**, **YLANG YLANG**, and **NEROLI**
* FORMULA: **CH₃C(O)OCH₂C₆H₅**
* ODOR: **FLORAL** and **FRUITY**
* USES:
* **PERFUME**
* **flavoring**
* **polishes**
BENZYL ACETATE
74
# **ESTERS**
REAGENTS USED
* Acetic anhydride
* Conc. H2SO4
* Alcohols
* Distilled water
* NaCl soln
* Sodium Bicarbonate soln
* Anhydrous sodium sulfate
