Worksheet: Crystallization
In this worksheet, we will practice describing the correct procedure for recrystallization and its use in the production of diffraction-quality crystals.
Q1:
Which of the following is not a method for increasing the crystallization rate?
- AEvaporation of solvent
- BScratching the inside of the flask
- CAdding a second solvent
- DGravity filtration
- ECooling the flask
Q2:
When performing a recrystallization, which of the following steps is not required?
- AThe solution is left to cool.
- BThe hot solution is filtered.
- CRecrystallized material is washed.
- DThe crude material is fully dissolved.
- EUnwanted solutions are disposed of safely.
Q3:
When applied to a solution, which of the following techniques could increase the purity of the resulting crystals?
- AEvaporation of solvent
- BCooling
- CScratching the inside of the flask
- DGravity filtration
- EAdding a seed crystal
Q4:
When recrystallizing a compound, for what purpose might the side of the flask be scratched with a glass rod?
- ATo accelerate the growth of existing crystals
- BTo accelerate primary nucleation
- CTo warm the solution
- DTo accelerate secondary nucleation
- ETo mix the solution
Q5:
Which of the following pieces of apparatus is not typically used in recrystallizations?
- A
- B
- C
- D
- E