A student carries out a titration to determine the concentration of a sodium hydroxide solution. They pipette 25.0 cm3 of the sodium hydroxide solution into a conical flask and add a few drops of phenolphthalein indicator. Dilute hydrochloric acid is then added from a burette until the end point is reached.
Which of the following shows the colour change that is seen in the conical flask at the end point of this titration?
colourless to pink
pink to colourless
yellow to red
red to yellow
Practise Edexcel GCSE Chemistry Acids with exam-style questions for Foundation and Higher tier. 100 questions, matched to the Edexcel GCSE Chemistry (1CH0) specification and written in Paper 1 and Paper 2 style. Every question includes a full worked solution and mark scheme, so you can see where marks are awarded rather than just whether you got the answer right.