Titration/practicals

Question 1

Suggest why a stopper needs to be put in the conical flask as quickly as possible-

Answer 1

To reduce the escape of the gas

Question 2

Explain the method of titration- 6 marker

Answer 2

Use a pipette and pipette filler to take 25cm3 sodium hydroxide ( it depends what acid they give u, say depending on the acid mentioned)and place it into a conical flask.
Place the conical flask on a white tile and the tip of the burette needs to be inside the conical flask.

Fill the burette with sodium hydroxide and record the intital volume.

Place a few drops of a suitable indicator inside the solution in the flask. (Such as methyl orange which turns from red to yellow, and phenolphthalein turns from colourless to pink)

Perform rough titration and take burette readings, and swirl the flask vigorously.

Quickly close the tap if you were to observe a sharp colour change and record the volume in which the colour changes at eye level to avoid parallax error.

repeat the titration at least 3 times with a fresh batch of sodium hydroxide.

Question 3

What is parallax error?

Answer 3

Not reading the measurements at eye level