S2 lessons on hydrogen, metals and acids, indicators, the pH scale, neutralisation, salts and acid rain. Tap a lesson to open it.
What do you know about hydrogen?
Hydrogen is an element.
This means that hydrogen is made up of atoms of one kind only.
The chemical symbol for hydrogen is H.
At room temperature hydrogen is a gas.
| Test Tube | Observation |
| 1 | |
| 2 | |
| 3 |
Before scientists do an experiment they make a hypothesis.
They write down what they think their experiment will show them and why they think that.
Collect a copy of the worksheet in the picture below.
Write down what you think (hypothesise) will happen: is hydrogen more dense or less dense than air?
Collect the following equipment:
Do the following or as instructed by your teacher:
Draw a labelled diagram of the two test tubes.
Copy and complete:
Hydrogen gas is more/less dense than air.
Write down what you think (hypothesise) will happen to the cobalt chloride paper and why.
Do the following:
Copy and Complete:
Cobalt chloride paper is b___ when dry and p___ when wet.
Write down what you think (hypothesise) will happen when hydrogen is burnt and why.
Do the following:
Copy and Complete:
When h_______ burns or explodes, it combines with o_____ from the air to form w____.
The chemical name for water is hydrogen oxide.
The word equation for the reaction is:
hydrogen + oxygen → water
The chemical formula for water is H2O.
Glue a picture of the Hofmann voltameter into your jotter, and copy this table:
| Electrode | Gas made | Test Used |
|---|---|---|
| Negative Electrode | ||
| Positive Electrode |
What happened when your teacher switched the electricity on?
Do the following:
Certain metals when they react with water are also capable of producing hydrogen from water.
Watch your teacher demonstrate the alkali metals reacting with water.
The video below shows the bigger pieces of alkali metals reacting with water as well as some that can't be done in school.
Copy the table below into your notes:
| Metal | Reaction with Water | Test for Hydrogen |
|---|---|---|
| magnesium | ||
| iron | ||
| calcium |
Collect the following equipment:
Watch your teacher demonstrate this experiment then follow the instruction below:
Do the following:
The metal that reacts most with water is c______.
The metal that reacts least with water is i___.
Some metals react with water to make h_______ gas.
Copy the table below:
| metal | observation |
|---|---|
| magnesium | |
| iron | |
| tin | |
| zinc | |
| copper | |
| aluminium |
Collect the equipment below:
Watch your teacher demonstrate the experiment then follow the instructions below:
To solve the anagram put the first letter of the metal's name in order of reactivity.
Watch the video below on making red cabbage indicator.
Use the information from the video to write a set of instructions for making red cabbage indicator.
Copy this diagram, and label it using the words:
Tripod Stand 100cm3 Beaker Red Cabbage Water
Copy the table below into your jotter.
| substance | colour change |
|---|---|
| water | no change |
| acid | purple → ___ |
| alkali | purple → _____ |
Collect the following items:
Watch your teacher demonstrate how to carry out this experiment then:
Answer the following questions in sentences in your jotter.
Copy and complete the notes below into your jotter.
An indicator is a dye that changes colour in different conditions.
Fruits and vegetables can be used to make indicators.
In class we used R__ C______ to make an indicator.
The colour changes I noticed were:
Acid P_____ → R__
Alkali P_____ → G____
Turmeric as an indicator.
Bicarbonate Soda as an indicator.
Universal indicator is a special dye that when added to a solution (liquid) is:
Red-orange in acid
green in neutral solutions
blue - purple in alkali
Copy the table below into your notes. You will need space for nine rows.
| Name of substance | Colour of Universal Indicator | pH number | Acid, alkali or neutral |
|---|---|---|---|
Collect the following equipment:
Follow the instructions below.
Copy and complete the notes below into your notes.
Answer the following questions in sentences.
When people get heartburn or indigestion they often take antacid tablets to neutralise the acid in their stomach.
Copy and complete.
Collect the Following Equipment
Watch your teacher demonstrate the experiment then follow the instructions on the worksheet
Collect the Following Equipment
Watch your teacher demonstrate evaporation then follow the instructions on the worksheet.
When an acid and an alkali are mixed in the correct proportions, a neutral salt solution and water are formed - this is called neutralisation.
Word equation:
Acid + Alkali → salt + water
Sodium hydroxide + hydrochloric acid → sodium chloride + water
Acid rain is caused by the gas sulphur dioxide which is produced when fossil fuels are burned.
It reacts with water in the atmosphere, then falls as 'acid rain'.
Burning coal and oil in power stations, factories and ships releases sulphur dioxide into the air.
Your task is to make a poster that answers one of the questions in the learning intentions.
You will find the following information helpful but you may also wish to do your own research.
Copy the table below into your notes.
| Metal Carbonate | Acid Used | Observation | Gas Produced |
|---|---|---|---|
| Calcium carbonate | |||
Collect the following equipment:
Copy and complete the note below.
