Acids, Bases and Salts
279 questions· page 1 of 28
The pH of dilute ethanoic acid is measured. The equation for the partial dissociation of ethanoic acid is shown.
Aqueous sodium ethanoate, , is added to the dilute ethanoic acid and the pH is measured again.
What is the initial pH of the dilute ethanoic acid and how does it change after the addition of the aqueous sodium ethanoate?
Options
| initial pH | change in pH after adding aqueous sodium ethanoate | |
|---|---|---|
| A | 3–4 | increases |
| B | 3–4 | decreases |
| C | 8–9 | increases |
| D | 8–9 | decreases |
Which element reacts with oxygen to produce an amphoteric oxide?
Options
A carbon
B copper
C sulfur
D zinc
A titration is completed.
of aqueous sodium hydroxide is added to a conical flask.
A few drops of methyl orange indicator are added.
Dilute hydrochloric acid is added slowly to the mixture until the colour changes.
Which row is correct?
Options
| apparatus used to add alkali | apparatus used to add acid | colour change of indicator | |
|---|---|---|---|
| A | volumetric pipette | burette | red to orange |
| B | measuring cylinder | burette | red to orange |
| C | volumetric pipette | burette | yellow to orange |
| D | volumetric pipette | measuring cylinder | yellow to orange |
The diagram shows the change in pH as a strong alkali is added to a weak acid.
of a strong alkali is added to a weak acid and a sample of the solution is tested separately with methyl orange and thymolphthalein.
Which row is correct?
Options
| methyl orange test | thymolphthalein test | |
|---|---|---|
| A | red | colourless |
| B | yellow | colourless |
| C | red | blue |
| D | yellow | blue |
Which row shows the equations for the dissociation of methanoic acid and of nitric acid?
Options
| methanoic acid | nitric acid | |
|---|---|---|
| A | ||
| B | ||
| C | ||
| D |
A student is making a sample of aqueous copper(II) sulfate. The student adds an excess of copper(II) oxide powder to warm sulfuric acid and stirs the mixture.
Which apparatus is used to separate aqueous copper(II) sulfate from the excess copper(II) oxide?
Options
A burette
B distillation apparatus
C filter funnel and paper
D measuring cylinder
How can a pure sample of barium sulfate be obtained from barium carbonate?
Options
A Dissolve it in dilute hydrochloric acid, add dilute sulfuric acid, filter and crystallise.
B Dissolve it in dilute hydrochloric acid, add dilute sulfuric acid, filter and wash.
C Dissolve it in water, add dilute sulfuric acid, filter and crystallise.
D Dissolve it in water, add dilute sulfuric acid, filter and wash.
Which statement is correct?
Options
A Ethanoic acid is a weak acid because when it is added to excess alkali not all of the ethanoic acid reacts.
B Ethanoic acid is a weaker acid than sulfuric acid because a smaller proportion of its molecules dissociate in aqueous solution.
C Hydrochloric acid is a stronger acid than ethanoic acid because hydrochloric acid always has a higher pH than ethanoic acid.
D Sulfuric acid is a strong acid because it produces two hydrogen ions for every molecule that dissociates.
Some properties of a solid oxide are listed.
- It reacts with dilute sulfuric acid giving a salt and water.
- It is insoluble in water.
- It reacts with aqueous sodium hydroxide.
Which oxide is being described?
Options
A aluminium oxide
B magnesium oxide
C phosphorus(V) oxide
D sodium oxide
Two compounds are dissolved separately in water.
When the two solutions are mixed, there is no observable change.
What are the two compounds?
Options
A sodium chloride and barium nitrate
B sodium chloride and lead nitrate
C sodium sulfate and barium chloride
D sodium sulfate and lead chloride