Nagwa uses cookies to ensure you get the best experience on our website. Learn more about our Privacy Policy.

Lesson: Dry Solvents

Worksheet • 8 Questions

Q1:

When cannulating a solvent, which of the following would not noticeably increase the flow rate between flasks?

  • APlacing more solvent in the solvent flask
  • BUsing a shorter cannula needle
  • CLowering the receiving flask
  • DBriefly exposing the receiving flask to vacuum
  • EIncreasing the gas flow to the solvent flask

Q2:

When removing a liquid from a Schlenk flask sealed with a rubber septum, what is the purpose of the bleed needle?

  • ATo allow introduced air to be flushed from the flask.
  • BTo extract liquid from the flask.
  • CTo introduce air into the flask.
  • DTo allow inert gas to leave the flask.
  • ETo lower the pressure inside the flask.

Q3:

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 receiving flask is too high.
  • BThe cannula is not inserted into the solvent.
  • CThe pressure in the solvent flask is too low.
  • DThe cannula is blocked.
  • EThe pressure in the receiving flask is too high.

Q4:

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?

  • AVacuum is applied to the receiving flask.
  • BA clamp is used to secure the bottle.
  • CThe bottle is connected to a supply of inert gas.
  • DTubing is flushed with inert gas before use.
  • EThe syringe is flushed with inert gas before use.

Q5:

When cannulation is complete, in which order should the following actions be performed?

  1. Open the receiving flask to the gas line.
  2. Remove the cannula from the receiving flask.
  3. Remove the cannula from the solvent.
  • A3, 1, 2
  • B1, 3, 2
  • C1, 2, 3
  • D2, 3, 1
  • E2, 1, 3

Q6:

What is the fastest method to stop the flow of solvent during cannulation?

  • ARemoving the cannula from the solvent
  • BDisconnecting the solvent flask from the gas line
  • CApplying vacuum to the solvent flask
  • DRaising the receiving flask
  • EOpening the receiving flask to the gas line

Q7:

When setting up a cannulation, in which order should the following actions be performed?

  1. Insert the cannula through the rubber septum.
  2. Attach a rubber septum to the solvent flask.
  3. Open the solvent flask to the gas line.
  • A3, 2, 1
  • B1, 2, 3
  • C2, 1, 3
  • D2, 3, 1
  • E3, 1, 2

Q8:

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
Preview