RP1 Flashcards
What is a standard solution?
A standard solution is a solution of known concentration.
How do you make a standard solution?
Measure, using a balance, the mass of solid required.
● Transfer this to a volumetric flask and rinse the remaining
weighing bottle content (with distilled water) into the flask
so no solid is lost.
● Add a volume of distilled water to dissolve the solid. Swirl
to mix.
● Then add more distilled water up to the line on the
volumetric flask. Invert multiple times to mix.
What equipment is used to carry out a titration?
● A pipette and pipette filler are used to accurately measure out the volume of a reactant before transferring it to a conical flask.
● A burette is used to add small volumes of one reactant to the other reactant (until the reaction has reached completion).
What is the weighing by difference technique?
● It is a method to weigh materials accurately.
● Mass of substance = Mass of weighing dish and substance - Mass of dish after substance has been transferred.
How do you carry out a titration?
● Once the pipette has been used to place one reactant into the conical flask, fill the burette with the other reactant. Record initial volume.
● Add a few drops of indicator to the conical flask.
● Open the burette tap and allow the reactant to flow into the conical
flask, swirling it to mix the contents.
● Close the burette tap once the expected colour change occurs. Use a
white tile so the colour change is easy to identify.
● Record final burette volume.
● Repeat until you get concordant results, then calculate a mean titre.
Why are acid-base indicators used?
To detect when a reaction reaches completion, usually by the presence of a colour change.
What are some common potential hazards and risks in the laboratory?
check!!
What are concordant results?
Titres that are within 0.1 cm3 of each other.
