Monitoring chemical reactions

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Question 41
Medium

A student neutralises barium hydroxide with dilute hydrochloric acid in a titration experiment.

a.

Look at the student's method for her experiment.

  • Measure 20.0 cm320.0\text{ cm}^320.0 cm3 of 0.0500 mol/dm30.0500\text{ mol/dm}^30.0500 mol/dm3 barium hydroxide into a beaker using a measuring cylinder.
  • Add a few drops of universal indicator to the barium hydroxide.
  • Fill the burette to the 0.00 cm30.00\text{ cm}^30.00 cm3 mark with dilute hydrochloric acid.
  • Quickly run the hydrochloric acid into the beaker until the indicator changes colour.
  • Repeat the experiment.

Describe and explain one improvement the student should make to her method to get a more accurate titration result.

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b.

The student repeats the experiment four times.

Look at the student's results.

Titration number1234
Volume of acid (cm3\text{cm}^3cm3)27.2025.0524.9525.00

Calculate the accurate volume of the acid that reacts with the alkali.

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c.

Look at the equation for the reaction between hydrochloric acid and barium hydroxide.

Ba(OH)2+2HCl→BaCl2+2H2O\text{Ba(OH)}_2 + 2\text{HCl} \rightarrow \text{BaCl}_2 + 2\text{H}_2\text{O}Ba(OH)2​+2HCl→BaCl2​+2H2​O

Use your answer from part (b)(i) to calculate the concentration of the dilute hydrochloric acid, HCl\text{HCl}HCl, that reacted with the 20.0 cm320.0\text{ cm}^320.0 cm3 of 0.0500 mol/dm30.0500\text{ mol/dm}^30.0500 mol/dm3 barium hydroxide.

Give your answer to 3 significant figures.

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Monitoring chemical reactions Questions

  1. GCSE
  2. /Chemistry
  3. /Monitoring chemical reactions