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Worksheet: Hazardous Reagents


When using a pyrophoric liquid, which of the following would not reduce the risk of the procedure?

  • AClamping the syringe when taking up the reagent
  • BUse of a cannula instead of a syringe
  • CUse of a glovebox
  • DMeasuring the reagent volume with the smallest suitable syringe
  • EOven drying glassware before contact with the reagent


When diluting an acid, why is it best to add the concentrated acid to water, instead of adding water to the concentrated acid?

  • ADiluting in this way prevents spillage of concentrated acid.
  • BConcentrated acid may damage the container.
  • CProducing an aqueous solution with a very low pH may cause counterions to undergo reduction-oxidation reactions.
  • DIt is easier to control the release of heat and avoid boiling of the solution.
  • EThe acid may precipitate if only a small volume of water is present.


When working with a large volume of pyrophoric reagent in a laboratory, which of the following is not a necessary precaution?

  • AOther people
  • BEmergency shower
  • CFire extinguisher
  • DGlovebox
  • EFace shield


When using a pyrophoric liquid, which of the following would not reduce the risk of the procedure?

  • ADiluting the material in heptane before quenching with water
  • BUse of n-butyllithium instead of t-butyllithium
  • CAvoidance of synthetic clothing
  • DUse of pentane instead of heptane as a solvent
  • EUse of n-hexyllithium instead of n-butyllithium


Which of the following can react in excess with aqueous potassium cyanide to produce a solution safe for disposal as non-hazardous aqueous waste?

  • ASodium hydroxide
  • BHydrochloric acid
  • CIsopropanol
  • DSodium hypochlorite
  • EPotassium dichromate


A reaction requires the use of 50 mL of a pyrophoric liquid. Which of the following methods for transferring the liquid would produce the greatest risk?

  • AFive transfers using a 20 mL syringe
  • BContinuous transfer via a cannula
  • CTwo transfers using a 50 mL syringe
  • DA single transfer using a 50 mL syringe
  • EA single transfer using a 100 mL syringe