Skip to content
MathsGenie logo
Open app

Course home

  1. A Level
  2. Chemistry AQA
  3. Question bank

Bonding

EasyMediumHard
1234567891011121314151617
Question 14
a.

Potassium carbonate reacts with dilute nitric acid as shown below:

K2CO3(aq)+2HNO3(aq)→2KNO3(aq)+CO2(g)+H2O(l) \text{K}_2\text{CO}_3(\text{aq}) + 2\text{HNO}_3(\text{aq}) \to 2\text{KNO}_3(\text{aq}) + \text{CO}_2(\text{g}) + \text{H}_2\text{O}(\text{l}) K2​CO3​(aq)+2HNO3​(aq)→2KNO3​(aq)+CO2​(g)+H2​O(l)

Give the simplest ionic equation for this reaction.

[1]
b.

The gas CO2\text{CO}_2CO2​ released from the combustion of fossil fuels can dissolve in seawater, causing ocean acidification.

State the chemical property of CO2\text{CO}_2CO2​ that causes acidification when it dissolves in water.

Give an equation to show the reaction of CO2\text{CO}_2CO2​ with water.

[2]
c.

Draw a diagram to show the shape of a molecule of H2O\text{H}_2\text{O}H2​O. Include any lone pairs of electrons in your diagram.

State the H−O−H\text{H}-\text{O}-\text{H}H−O−H bond angle.

Explain this shape and bond angle in terms of electron pair repulsion.

[4]
d.

The initial rate of the reaction between hydrogen peroxide and iodide ions (the iodine clock reaction) can be monitored by measuring the time taken for a fixed amount of iodine to be produced in the presence of a starch indicator and a small, known amount of sodium thiosulfate.

Describe an experiment to investigate the effect of the concentration of iodide ions on the initial rate of this reaction.

Include:

  • a brief outline of your method
  • how you will measure the time taken for a fixed amount of iodine to be formed
  • how you will present your results in graphical form
  • a sketch of the graph that you would expect.
[6]

Bonding Questions

  1. A Level
  2. /Chemistry
  3. /Bonding