exp 3 post lab

Question 1

SIMPLE VS STEAM DISTILLATION

characteristics of sample used

Answer 1

SIMPLE
- Homogenous
- nonvolatile solute + volatile solvent
- OR 2 miscible liquids with one more volatile than the other

STEAM
- Heterogenous
- water + another substance insoluble in water, higher boiling point than water, and slightly volatile

Question 2

SIMPLE VS STEAM DISTILLATION

main principle + law it follows

Answer 2

SIMPLE
- evaporation and separation of sample based on differences in boiling points (20 - 25C difference)
- Raoult’s Law

STEAM
- co-distillation of water and desired component
- Dalton’s Law of Partial Pressure

Question 3

SIMPLE Distillation employs what law?

• states that the ____ ____ of a compound is ____ when it becomes a ____ of a ____

Answer 3

RAOULT’s LAW

• vapor pressure
• lowered
• part
• solution

Question 4

In the experiment, simple distillation was done between ___ and ___

Answer 4

• ethanol and water

Question 5

what happens if the boiling difference between 2 substances in SIMPLE DISTILLATION is small?

Answer 5

pwede sabay mag boil yung substances sa mixture so di ma s-separate

Question 6

STEAM Distillation employs what law?

• wherein ___ component of the mixture exerts a _____ ____ that is _____ of the ___ ___ of the ____ components
• the combination of the ____ ___ of both components is _____ than each of their ____ ____ ___

+ Formula

Answer 6

DALTON’s LAW OF PARTIAL PRESSURE

• each
• vapor pressure
• independent
• vapor pressure
• other
• boiling points
• lower
• individual boiling points

P total = P water + P other component

Question 7

SIMPLE VS STEAM DISTILLATION

temperature at which the mixture boils

Answer 7

SIMPLE
- starts upon reaching the BP of the desired substance or the component that is more volatile/with the lower BP

STEAM
- starts at a temp lower than the BP of both components in the mixture

Question 8

SIMPLE VS STEAM DISTILLATION

contents of distillate

Answer 8

SIMPLE
- distillate should ONLY contain the desired/lower BP substance

STEAM
- contains both the water and the desired substance (other) as oily droplets

Question 9

in STEAM distillation, what is the appearance of the separatory funnel that collects the distillate?

*which of the 2 components is more abundant?

Answer 9

2 layers: water and the other component

*mas madaming water compared sa other component
*small portions of the other component dissolves in the water

Question 10

SIMPLE VS STEAM DISTILLATION

application (suitable for what substances?)

simple (1)
steam (5)

Answer 10

SIMPLE
- separating substances with WIDE DIFFERENCE in boiling points (minimum interval lang yung 20-25)

STEAM
- mixture is liquid
- separate substances that are volatile and water-immiscible
- sensitive to heat
- decompose at high temperature
- mixtures containing large amounts of nonvolatile material (plant sample + water)

Question 11

SIMPLE VS STEAM DISTILLATION

limitations (2 per each)

Answer 11

SIMPLE
1. cannot be used on those w close boiling pts
2. cannot be used on those that decompose at their BP

STEAM
1. cannot be used on those that react with water or decompose with water contact
2. nonvolatile compounds

Question 12

SIMPLE VS STEAM DISTILLATION

set-up

simple

Answer 12

SIMPLE
- use of thermometer
- receiver: beaker/erlenmeyer flask

STEAM
- does not require thermometer
- receiver: separatory funnel/erlenmeyer flask

Question 13

How to keep condenser cold?

Answer 13

water pump to ice bath

Question 14

why does ESSENTIAL OILS use steam distillation?

Answer 14

steam can penetrate cells of plant sample and release the oils from their packets

Question 15

why should the plant samples be cut into smaller pieces before distillation?

Answer 15

increases the surface area of contact with the water, making the process more efficient

Question 16

SALTING OUT PROCESS

• when used?
• allows _____ removal of ____ ___ from ____ through ____ the solubility of the oil from the water

Answer 16

• steam distillation: after the separatory funnel filled up with mixture of water and essential oils (2 layers: aq and organic)
• maximum removal of essential oil from water through reducing the solubility

Question 17

IMFA between water and essential oil

IMFA between water and salt

Answer 17

LDF

ion-dipole (stronger)

• so water would like to interact more with salt kaya si water lalayo kay water

Question 18

DALTON’s LAW OF PARTIAL PRESSURE

• dictates how water ____-___ with the _____ compound
• states that the ____ VP of the ____ must equal the _____ _____ at ____Celsius

Answer 18

• co-distills
• desired
• total
• mixture
• atmosphere pressure
• 25

Question 19

PRESSURE is = to ____ atm, ____ mmHg, and ____ torr

Answer 19

1 atm
760 mmHg
760 torr

Question 20

Dalton’s Law of Partial Pressures

formulas (2)

Answer 20

P total = P water + P other component

(n oil) / (n steam) = (P oil) / (P steam)

n oil = no. of moles of oil vaporized from mixture
n steam = no. of moles of steam produced during distillation

Question 21

Molar Mass of Water

Answer 21

18.016 g/mol

Question 22

number of moles formula

Answer 22

n = (mass of substance) / (molar mass of substance)

Question 23

the vapor pressure of each compound _____ as temperature ____ or ____

thus, ____ at which distillation occurs should be _____

Answer 23

• vary
• increases
• decreases
• temperature
• specified

Question 24

in mole ratio “n oil: n steam”, what does a low and high mole ratio indicate?

Answer 24

LOW MOLE RATIO: unting oil lang nakuha, mas madaming tubig

HIGH MOLE RATIO: maraming oil nakuha, unting tubig lang

Question 25

In problem solving, what if volume ang bigay instead of moles, vapor pressure, or mass?

Answer 25

use density formula

Question 26

PAALALA sa problem solving?

Answer 26

always check yung VP ng water and oil if equal to 760 mmHg/torr ALSO check yung units if same ba or if ano hihingi or if naka atm or mmHg

Question 27

Is P atm always 1 atm?

Answer 27

Yes, automatically IF 25 C pero kapag di given, you can double check by getting the P total or P water + P oil