pH & Neutralization — Drills · Grade 11 Science
Chapter: Acids, Bases & TitrationWhat these drills covers
By the end of pH & Neutralization you should be able to:
- I can use the pH scale to classify a solution and connect its pH to the concentration of hydrogen ions.
- I can explain a neutralization reaction and predict the products when an acid reacts with a base.
6 questions, multiple choice, numeric and written answer, each with a worked explanation.
Vocabulary used: pH scale, pH, neutralization, salt, indicator, titration.
Problem 1
- slightly acidic
- neutral
- slightly basic
- strongly basic
Answer and explanation
slightly acidic
A pH just below 7 is slightly acidic; 6 is a little below neutral.
Problem 2
Answer and explanation
7
At 25°C, Kw≈10⁻¹⁴ and equal hydronium and hydroxide concentrations give pH≈7. Neutral pH changes with temperature.
Problem 3
Answer and explanation
8
pH = −log(1 × 10⁻⁸) = 8, which is slightly basic.
Problem 4
- gas only
- salt
- stronger acid
- metal
Answer and explanation
salt
H⁺ and OH⁻ form water; Na⁺ and Cl⁻ remain dissolved. They correspond to sodium chloride, a salt; solid salt need not precipitate.
Problem 5
Answer and explanation
Add a standard base to a measured acid volume and record the volume near the chosen endpoint. Use the balanced reaction ratio and standard concentration to calculate the acid amount and concentration. The indicator endpoint approximates stoichiometric equivalence; select a suitable transition range and assess overshoot and volume uncertainty rather than assuming a color change is exact equivalence.
Problem 6
Answer and explanation
1000 times
The activity ratio is 10^(4−1)=1000. The ratio of total titratable acid amounts is not determined by this pH comparison alone.