Year 7 · Science · Acids and alkalis · Lesson 1
Acids, alkalis and the pH scale
Acids and alkalis, the pH scale from 0 to 14, everyday examples, and indicators including litmus, universal indicator and red cabbage.
17-minute video lesson
Teaching, worked examples and 20 practice questions solved step by step.
Watch free for a monthWhat your child will learn
- Use the pH scale
- Classify substances as acid, neutral or alkali
- Describe indicator colours
- Test pH safely
The method
- Goggles.
- Add indicator.
- Compare chart.
- Read pH.
Key words: acid, alkali, neutral, pH, indicator, universal indicator.
Worked examples
The first three practice questions from the lesson, with every step.
Question 1
What range does the pH scale cover?
- Step 1: 0 to ?
Answer: 0 to 14
Question 2
What pH is neutral?
- Step 1: Middle
Answer: 7
Question 3
Is pH 3 acid or alkali?
- Step 1: Below 7
Answer: acid