Separations And Purifications

Question 1

To protonate (add H) we need

Answer 1

Acidic environment

Question 2

To deprotonate (remove H) we need

Answer 2

Basic environment

Question 3

What are paper and thin layer chromatography used for?

Answer 3

For identifying compound by measuring the distance traveled by sample.

Rf (retention factor) = dis traveled by molecule/dis traveled by solvent

Question 4

What are the phases like paper/TLC and reverse phase chromatography?

Answer 4

Paper/TLC:

Stationary Phase: Polar
Mobile Phase: Non polar

Reverse-Phase:

Stationary Phase: non Polar
Mobile Phase: polar

Question 5

What is gel filtration used for?

Answer 5

Used for identifying compounds based on their size. The large the compound is the slowest it will travel i.e. smallest compounds will travel the most distance

Question 6

What is true about amine (NH3+)?

Answer 6

Protonated or acid form has positive charge
Deprotonated is neutral

Question 7

What’s true about carboxylic acid?

Answer 7

Protonated form is neutral
Deprotonated form is negatively charged

Question 8

What’s isolelectric point (pi)?

Answer 8

It’s the pH when the compound has net charge of 0