Year 11 CHE titration questions

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11 questions
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(ii) In a titration, a student adds 25.0 cm3 of barium hydroxide solution to a conical flask.
Give a reason why it is better to use Y rather than X.

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(b) The student uses methyl orange indicator in the titration.
(i) State the colour of methyl orange in barium hydroxide solution.

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(ii) Give a reason why universal indicator is not suitable for use in a titration.

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The student adds some dilute nitric acid to a burette and does the titration.
The equation for the reaction is
Ba(OH)2 + 2HNO3 → Ba(NO3)2 + 2H2O
The student finds that 21.50 cm3 of nitric acid of concentration 0.600 mol/dm3 neutralises 25.0 cm3 of barium hydroxide solution.
Calculate the concentration, in mol/dm3, of the barium hydroxide solution.

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(d) State why sulfuric acid would not be a suitable acid to use in this titration.

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Question 2 a)

A student investigates the reaction between sodium hydroxide solution and dilute sulfuric acid.
He does a titration to find the concentration of the sulfuric acid.
This is his plan for the titration. There are some mistakes and omissions in his plan.
· rinse a conical flask with the sodium hydroxide solution · use a measuring cylinder to measure out 25 cm3 of the sodium hydroxide solution and add it to the conical flask · add a few drops of methyl orange indicator to the conical flask · rinse a burette with water and then fill it with the sulfuric acid · add the acid from the burette to the conical flask until the indicator changes colour at the end-point of the titration · record the final burette reading


(a) Give the colour change of the methyl orange indicator at the end-point.

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(b) Describe four changes that the student could make to improve his plan.

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(c) The student then does the titration correctly.
He finds that 16.70 cm3 of the dilute sulfuric acid neutralises 25.0 cm3of sodium hydroxide solution of concentration 0.200 mol/dm3
The equation for the reaction is
2NaOH + H2SO4 → Na2SO4+ 2H2O
Calculate the concentration, in mol/dm3, of the sulfuric acid.

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A student does a titration using dilute sulfuric acid to find the concentration of a solution of potassium hydroxide.

The student adds 25.0 cm3 of the potassium hydroxide solution to a conical flask. He then adds a few drops of methyl orange indicator.
The student does the titration four times.

(a) (i) Name the piece of apparatus the student should use to add the potassium hydroxide solution.

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(ii) What is the colour of methyl orange in an alkaline solution?