Worksheet: Dry Solvents
In this worksheet, we will practice describing the transfer of dry solvents by cannulation and other methods, assessing hazards and common errors.
When a syringe is used to remove a liquid from a bottle or Schlenk flask containing an inert atmosphere, which of the following steps is not required?
- AThe bottle is connected to a supply of inert gas.
- BA clamp is used to secure the bottle.
- CVacuum is applied to the receiving flask.
- DThe syringe is flushed with inert gas before use.
- ETubing is flushed with inert gas before use.
When removing a liquid from a Schlenk flask sealed with a rubber septum, what is the purpose of the bleed needle?
- AAllowing inert gas to leave the flask
- BIntroducing air into the flask
- CAllowing introduced air to be flushed from the flask
- DExtracting liquid from the flask
- ELowering the pressure inside the flask
Which of the following items of glassware is least useful for performing a cannulation?
- AOne-necked flask
- BDry solvent bottle
- CTwo-necked flask
- DSchlenk flask
- EThree-necked flask
A student sets up a cannulation but finds there is no solvent flow. Which of the following is least likely to be the cause of the problem?
- AThe pressure in the receiving flask is too high.
- BThe cannula is blocked.
- CThe cannula is not inserted into the solvent.
- DThe pressure in the solvent flask is too low.
- EThe receiving flask is too high.
When cannulating a solvent, which of the following would not noticeably increase the flow rate between flasks?
- AUsing a shorter cannula needle
- BIncreasing the gas flow to the solvent flask
- CLowering the receiving flask
- DBriefly exposing the receiving flask to vacuum
- EPlacing more solvent in the solvent flask
What is the fastest method to stop the flow of solvent during cannulation?
- AOpening the receiving flask to the gas line
- BApplying vacuum to the solvent flask
- CRaising the receiving flask
- DDisconnecting the solvent flask from the gas line
- ERemoving the cannula from the solvent
When cannulation is complete, in which order should the following actions be performed?
- Open the receiving flask to the gas line.
- Remove the cannula from the receiving flask.
- Remove the cannula from the solvent.
- A1, 3, 2
- B2, 3, 1
- C3, 1, 2
- D2, 1, 3
- E1, 2, 3
When setting up a cannulation, in which order should the following actions be performed?
- Insert the cannula through the rubber septum.
- Attach a rubber septum to the solvent flask.
- Open the solvent flask to the gas line.
- A3, 2, 1
- B2, 3, 1
- C1, 2, 3
- D2, 1, 3
- E3, 1, 2