C4: Quiz 3
1) What ion do acids form when they dissolve in water?
2) Hydrochloric acid is HCl. Write the dissociation equation for HCl dissociating to produce a H+ ion.
3) Nitric acid is HNO3. Write the dissociation equation for HNO3 dissociating to produce a H+ ion.
4) What is the difference between a strong acid and a weak acid?
5) Hydrochloric acid is a strong acid and ethanoic acid is a weak acid. If we had two beakers of the two acids with the same volume and concentration, which acid would have the lower pH? Explain your answer.
6) Ethanoic acid is a weak acid. The equation for the dissociation is shown below.
a) What does the symbol in the middle mean?
b) This dissociation will reach a dynamic equilibrium; what does dynamic equilibrium mean?
c) For the same concentration, will a stronger acid produce more H+ ions than ethanoic acid? Will the pH of the stronger acid be lower or higher than the pH of ethanoic acid? Explain your answer.
7) As we go down the pH scale by 1 for acids (e.g. from 4 to 3), by what factor does the concentration of H+ ions increase by?
8) An acid has a concentration of 9 g/dm3 and a pH of 4. The acid is diluted resulting in it having a concentration of 0.9 g/dm3. What is the pH of the diluted acid?
9) An acid has a concentration of 25 g/dm3 and a pH of 2. The acid is diluted resulting in it having a concentration of 0.25 g/dm3. What is the pH of the diluted acid?
10) An acid has a concentration of 3 mol/dm3 and a pH of 1.6. The acid is diluted resulting in it having a concentration of 0.003 mol/dm3. What is the pH of the diluted acid?
11) An acid has a pH of 2.1 and a concentration of 5 mol/dm3. I add some water to the acid, which results in the concentration becoming 0.0005 mol/dm3. Find the pH of the solution after I have added some water.