Lesson 2
Acid reactions
Objectives:
Know the meaning of neutralisation.
Know the products of neutralisation between acid and alkali.
PART A
Read and copy this paragraph:
Acids and alkalis are a bit like opposites, so when they mix together there is a chemical reaction. If they are added together in just the right amounts, the acid and alkali cancel each other out - this is called neutralisation. At the end of the reaction two new substances are made - a salt and water.
We can show this reaction using a word equation:
Acid + Alkali --> A salt + Water
PART B
Watch this experiment:
PART C
Draw a diagram to show what happened in this experiment. Make sure you use colours to show how the colour changed from the start to the finish.
PART D
Copy this:
Results of experiment
In this experiment, hydrochloric acid was added to sodium hydroxide (an alkali). At the start of the experiment, the hydrochloric acid turned universal indicator red and the sodium hydroxide was blue/purple. They were added together in exactly the right amounts and the universal indicator turned lime green. This showed that the liquid was now neutral.
PART E
Watch this video about how to name salts.
PART F
Copy this table onto paper and try to fill in the names. If you find it difficult - the video in part G will help you.
PART G
Video to help you to fill in the table.
PART I
Watch this experiment. While you watch write down the names of any chemicals that were used on your piece of paper.
PART J
Copy these questions and answer them from what you watched in the video.
- What was the name of the acid used?
- What was the name of the base (the other chemical)?
- What was the colour of the liquid when the acid and the base reacted together?
- How did the teacher remove the extra black powder from the liquid?
- What was the name of the salt made?
- How did the teacher get pure dry crystals at the end?