Science lesson plan · 8th grade (Year 9 in England) · 45 minutes
Neutralisation and naming salts
Chemical reactions, acids and bases
CCSS NGSS.MS-PS1-2CCSS NGSS.HS-PS1-2England: KS3 Chemistry: Chemical reactionsEngland: KS4 Combined Science: Chemical changes
Objective and success criteria
Students will: Neutralisation and naming salts.
- I can answer questions on today's skill on my own, without help.
- I can explain each step and say why it works.
- I can check my answer and spot a mistake.
Before and after
Needs first: Acids, alkalis (bases) and the pH scale; Reactants, products and word equations
Leads to: The reactivity series and displacement; Titration calculations
Materials: Teacher demo or video, Indicator color chart, Mini whiteboards, A diagram or short video clip of the idea, Printed student sheet (below).
Warm-up · 5 min
- Quick retrieval from earlier learning (Acids, alkalis (bases) and the pH scale; Reactants, products and word equations). Students answer on mini whiteboards.
- Show answers together and note who needs support in the main task.
- Complete the word equation: magnesium + oxygen → ___ (carbon dioxide / magnesium oxide / magnesium chloride / magnesium carbonate) → magnesium oxidePrompt: A metal reacting with oxygen makes a metal oxide.
- Which of these is an alkali (base)? (vinegar / orange juice / hydrochloric acid / sodium hydroxide solution) → sodium hydroxide solutionPrompt: Many alkalis are hydroxides.
- Universal indicator turns red in a solution. What does this tell you? (It is neutral / It is pure water / It is a strong alkali / It is a strong acid) → It is a strong acidPrompt: Red is at the low-pH end of the colour chart.
Hook · 5 min
- Drop an antacid tablet in water (or show a clip) and ask whether a new substance is being made.
- Share the objective: Neutralisation and naming salts. Read the success criteria together.
I do: model it · 10 min
- Work through the example out loud, saying why you do each step, not just what you do.
- Example: Name the salt: potassium hydroxide + nitric acid → ___ + water
- Step 1: nitric acid → nitrate
- Step 2: So the answer is: potassium nitrate
- Answer: potassium nitrate
- Pause after each step and ask a student to say what comes next.
We do: guided practice · 10 min
- Do these together. Students try each step on whiteboards before you reveal it.
- Use the hints as prompts rather than giving the answer.
- Name the salt: magnesium + hydrochloric acid → ___ + hydrogen (magnesium nitrate / magnesium oxide / magnesium sulfate / magnesium chloride) → magnesium chloridePrompt: The first part of the salt's name comes from the metal.
- Which gas is produced when a carbonate reacts with an acid? (carbon dioxide / oxygen / hydrogen / nitrogen) → carbon dioxidePrompt: It turns limewater milky (cloudy).
You do: independent practice · 10 min
- Students work on the student sheet. Circulate and check the first two answers of every student early.
- Students who finish: write a question of their own for a partner, with the answer.
The 8 questions are on the student sheet below, with answers in the key.
Exit ticket · 5 min
- Two questions on their own. Sort answers into got it / nearly / not yet to plan the next lesson.
- What are the products when an acid neutralises an alkali? (oxygen and water / a salt and hydrogen / a salt and water / an acid and a base) → a salt and waterPrompt: acid + alkali → … + …
- 20 cm³ of an acid starts at pH 1. An alkali is added 5 cm³ at a time. The pH readings are 1, 3, 4, 6, 7. What total volume of alkali made the solution neutral, in cm³? → 20 cm³Prompt: Neutral means pH 7.
Watch out for
- Everyday meanings of words getting in the way of the science meaning: define key words explicitly.
- Remembering facts without the reason: ask "why?" and "what is the evidence?"
Support and stretch
Support
- Review first: Acids, alkalis (bases) and the pH scale.
- Use concrete materials: teacher demo or video.
- Give the first step of each question, or a partly worked example to finish.
- Pair with a confident partner for the guided practice.
Stretch
- Move on to: The reactivity series and displacement; Titration calculations.
- Explain a common mistake in writing and how to fix it.
- Write a word problem that uses today's skill, then solve a partner's.
Homework and more practice
Free online practice with hints and printable worksheets for this skill: eurekami.com/science/grade-8.
Free lesson plan from eurekami.com/lesson-plan-builder