Notes:
This is a series of experiments given after the ‘God with no Hands’ parallel to ‘Features of the Earth’ and ‘The Sun and the Earth’,to help build the child’s imagination to see that which is not readily experienced. We show the results and effects of phenomena which shape physical geography, e.g. erosion. We want to show that these effects relate to events in the past.
For organisational purposes we have grouped the effects into four sub-sections which we do not share with the children. We relate each set of experiments to the story of the God with No Hands, quoting or paraphrasing it, leave some time between giving the story and beginning the experiments so you can follow the interests that emerge from the story.
The experiments are given in an impressionist manner, we don’t tell them what the substances are but tell them later if they ask, the techniques involved are not stressed, the focus is on whether or not they ‘like each other’. If they children wish to repeat then we given them the names and information about the techniques and processes, supported by the Geography Command Cards, in an activity which involves manipulation and reading.
Different Ways of Combining
Method:
Six experiments which can be done together.
Refer back to the part of the ‘God with No Hands, when God gave other instructions, each of the special particles were given different laws…in this way they formed different groups. Lets see which of these particles like or love each other’
Experiment 1
Material Description:
First tray, two identical glasses with salt in one and tepid water in the other,glass rod
Process:
Pour the salt into the water, ask the child to stir. Ask ‘Lets see if these particles like each other. Do you think they need a bit of help?’ (yes)
Experiment 2
Material Description:
Second tray, two identical glasses with tepid water in one and half teaspoon finely crushed copper sulphate crystals in the other, glass rod
Process:
Pour the water into the coppersulphate and invite the child to stir Ask ‘Do these particles like each other. Do you think they need a bit of help?’ (yes)
Experiment 3
Material Description:
Third tray, an acid resistant dish (e.g. porcelain crucible) with hydrochloric acid (1 part water to four parts acid) and a chip of marble, gloves
This is a dangerous experiment – keep the hydrochloric acid in a closed container, keep the children away from the acid and the fumes
Process:
Let the children handle the marble chip and tell them they will not touch it anymore, then very carefully pour the acid into the marble chip. Ask ‘Do these particles could like each other enough to merge? Do you think they need a bit of help?’ It may take up to ten minutes (yes)
Remove the experiment when complete, pouring the acid down the drain with lots of running water.
Experiments 4a and 4b
Material Description:
Fourth tray, a rack for test tubes with four test tubes;
4a The first pair water and and inch of sand contain and a bung
4b and the second pair water and half a teaspoon of chalk powder, kaolin and a bung
First,pour the sand into the water, place on the bung invite the child to shake it Ask ‘Do these particles like each other. Do you think they need a bit of help?’ (eventually they will separate, no).
Process: Results:
Pour the chalk into the water, place on the bung invite the child to shake it Ask ‘Do these particles like each other. Do you think they need a bit of help?’ (eventually they will separate, no)
Note:
You can refer to the calcium carbonate being deposited on the bottom of the sea in the Story of Creation
Experiment 5
Material Description:
Fifth tray, two identical saucers one with a teaspoon of sand and the other with a quarter of a teaspoon of fine iron filings, and a magnet hidden in a white handkerchief and a plastic spoon for mixing.
Process:
Transfer the iron filings into the sand and invite the child to mix them with the spoon. Say, ‘At first they seem to like each other, like people sitting side by side at a football match, but at the end they go their separate ways?’ Produce the handkerchief with the magnet, to hide the magnet at first, and separate the sand and the iron fillings.
Experiment 6
Material Description:
Sixth tray, two identical saucers one with a teaspoon of flour of sulphur and the other with a quarter of a teaspoon of fine iron filings, and a magnet hidden in a white handkerchief and a plastic spoon for mixing.
Process:
Transfer the iron filings into the sulphur and invite the child to mix them with the spoon, Say, ‘These are like people on a bus, they sit side by side, but when they get to their stop they go their separate ways?’ Produce the handkerchief with the magnet and separate them.
Let the children help to tidy the experiments, apart from the third under running water.
After the lesson:
Later give the terms ‘solution’ for the first three experiments and ‘matter in suspension’ and ‘deposit’ for 4a/b, ‘mixture’ for 5 and 6
Notes:
From the perspective of the chemist we are showing physical changes which are either reservable or not.
Aim:
To show how substance change when they combine, dissolving, mixing and being separable while others neither dissolve nor mix.
Experiment 7a
Material Description:
Two test tubes on a stand, or two test tubes spread over two stands
One test tube with a concentrated solution of 2tsp of copper sulphate in 50ml of 60 degree water
One test tube with an inch of ammonia
Method:
Pour the ammonia into the copper sulphate solution. Say, ‘Something drops to the bottom and in makes something new’. Do not shake
Notes:
To demonstrate precipitation
Experiment 7b
Material Description:
Two test tubes on a stand, or two test tubes spread over two stands
One test tube with pinch of potassium dichromate
One test tube with lead nitrate in liquid form, or mix 1.5 tsp of lead nitrate crystals in a small amount of water
Method:
Slowly pour the liquid nitrate into the potassium dichromate solution. Say, ‘Watch hat happens, it is turning cloudy, we are making something new’. Do not shake. Give the term ‘precipitate’, it means, ‘tiny particles of solid suspended in a liquid’. It shows a chemical reaction has happened, this is when chemicals react together to produce one or more new substances. A chemical reaction cannot be reversed.
Notes:
To demonstrate precipitation
Aim:
To show how substance change when they combine, dissolving, mixing and being separable while others neither dissolve nor mix.
Experiment 8
Material Description:
A cup and a saucer, a few drops of ammonia on cotton wool, prepared in advance and wrapped up in cling film.
A little drop of iron chloride or hydrochloric acid. gloves
Method:
Ask the children to check if anything is on the cup and saucer (no)
Wearing gloves put the cotton wool on the base of the saucer and the drop of acid in the cup
Place the saucer on top of the cup for a minute or two and then lift it off
Say, ‘Oh, we’ve made some smoke’
Notes:
Tiny crystals of sulphur have been produced which are floating in the air, this is the sign that a chemical reaction has taken place.
Experiment 9
Material Description:
Heat resistant tray with a pyrex container
100g sugar
50ml sulphuric acid in a closed bottle
Glass rod for stirring
gloves
tongs for holding the container
Method:
Outside
Fill the container 1/3 full of sugar, pour the acid onto the sugar and mix them together with a glass rod.
Describe the changes you see in terms of colour, smoke, solidification, formation of black substance, Say, ‘Oh, we’ve made some carbon or coal
Leave it to cool
Notes:
Safety; Avoid the fumes, do not touch the carbon, it is very hot.
After an hour or so it will have cooled sufficiently for the children to touch.
Notes on all experiments
If it is possible to do so safely, keep the experiments available for the next few days for the children’s further observation and questions. Anticipate the question,
- Can we reverse the reactions? Mixtures, suspensions and heated solutions would separate, the others are not reversible
- Is there a limit to what solutions can hold? Try to see how much of a substance can be dissolved, e.g. how much salt or sugar can be dissolved in a small amount of water, with heat make a super-saturated solution, heat helps boost waters power to dissolve.
- At a later stage give more information about the experiments.
- The choice of experiments will be determined by the children’s level of normalisation and the numbers of experiments in one sitting.
- Keep the experiments in clusters, e.g. (1)solutions, (2)suspensions, (3)mixtures, (4)precipitation and crystallisation and then (6) chemical reactions
The Three States of Matter
This is given to children who wish to explore the laws given to properties further.
Method:
Pick up from the story of God with No Hands, when the properties of matter are given laws, recap these, wither reading directly from the story or paraphrase.
Experiment 1 – solids
Material Description:
Iron bar, piece of wood and a piece of tile on a tray, a hammer and a heavy cloth
Method:
Say, ‘Lets have a look at these solids and see if it is true that the particles cling very closely together’. With the children try to bend, stretch and break them to see if you can alter their shape, ‘We can’t change the shape but the laws say you can if you apply a strong force, so say, I’‘ll try with a hammer, wrap the tile in cloth and hit it with a hammer on the floor, say to the children, ‘What have we here, we still have solids but now they are in smaller pieces, particles of solids do cling close together, we can only separate them if we use force.
Experiment 2 – liquids
Material Description:
Wide transparent bowl on a try and a towel
Method:
Move your hands freely through the water, saying, ‘The particles of the liquid don’t cling so closely together, they follow the law that was given to them, it’s as if they say, “be my guest”, the particles of liquids roll over each other’.
Experiment 3A – liquids
Material Description:
Collection of differently shaped glass containers on a tray, have one long tall one and a round one and a jug of coloured water, tissue paper or cloth
Method:
Pour the water into the containers, saying, ‘We know solids have a shape of their own, but look at the liquids, they roll over each others and don’t have any shape of their own, the liquids take the shape of whatever vessel we pour them into‘
Experiment 3B- liquids
Material Description:
One container pierced with holes in the base and the lower parts of the side, a large empty bowl, a jug of water and a prism
Method:
Part 1
Say, ‘We discovered that the liquids do not have a shape of their own, but watch‘. Pour the water quickly into the container and note how the water falls, sideways and downwards. Wait until the container is empty.
Part 2
Ask the child to stretch out her and and let her feel the force of the solid pushing down, then put the prism beside the child’s hand to show that solids exert no sidewards force, say, ‘It seems that the solids press downwards only’.
Notes:
An alternative is to tape up the holes in the container and fill it with water first, reveal them and see how the water flows out more slowly.
Experiment 4 – gas
Material Description:
Wide transparent bowl on a try and a towel
Method:
Saying, ‘What about the gasses, they seem move in all directions, Dance in all directions, waking your arms and legs, say, “Their particles do not cling closely and they don’t have a shape of their own, they let us move around however we like’.
Experiment 5 – gas
Material Description:
Perfume or essential oil
Method:
Walk behind the children discretely releasing the scent, the children experience the smell as the gasses let it travel in every direction. Comment on it.
Experiment 6 – gas
Material Description:
Tumbler of water filled with water to the brim, a piece of thin but strong cardboard, a basin, lots of paper towels, a plastic mat
Method:
Slide the cardboard over the top of the tumbler and quickly turn it over above the basin, say, ‘We know that the liquids press downwards, but here we can see that the liquids press upwards, so it prevents the liquids from escaping.’
Notes:
- Give these experiments with an emphasis on the impressionistic approach, using personification, to arouse the children’s interest and admiration, to appeal to their imagination and emotions. Be dramatic.
- By examining the three states of matter together, in one sitting the mind of the child can contrast the different states, this is not only intellectually valuable but it also holds her attention.
- Follow the child’s interest when deciding how to use the story and when to give the presentation.
- Show this to a small group of children and wait for other groups of children to request a further presentation.
- This set contains nothing dangerous, an older child can show children who have not had the demonstration, let the older child collect the pieces of equipment themselves from different shelves, and not take pre-prepared trays to develop intellectual order.
Further States of Matter
On a different occasion say, ‘Let’s look more closely at the solids and liquids’.
Experiment 1
Solids – rigidity, elasticity and plasticity
Material Description:
Two tray, one with, an iron bar, rubber tubing, a plasticine bar, the other with a styrofoam ball, a tennis ball and a ball of plasticine
Method:
‘We know it is very difficult to change the shape of the solids, unless pressure is applied, so let’s see how these behave.’
Try to bend the iron bar and comment that it doesn’t change shape. The tubing, which changes but when the pressure is removed it goes back to it’s original shape, now try the plasticine bar, it changes shape and keeps the new shape.
Repeat this with the three balls. The children discover that some solids do not change shape, others change temporarily others permanently change shape.
Later, when the children are working with this on their own give the new language; ‘Solids that keep their shape, even under pressure are ‘rigid’, solids that change their shape and return to their original shapes when the pressure is removed are elastic, solids that change their shape and retain the new shape when the pressure is removed are ‘plastic’.
Aim:
Introduce new concepts about solids rigidity, elasticity and plasticity of solids
Experiment 2
Liquids – fluidity and viscosity
Material Description:
Test tube stands with three test tubes fixed, each contain similar amounts of water, oil and honey in contrasting colours, a piece of perspex and a large bowl.
Method:
‘We discovered that liquids press downwards and sideways and roll over each other, let’s see if they all roll over each other in the same way.’
Hold the glass over the bowl in an oblique position, tip the opening of the test tubes over the perspex and allow the liquid to flow. Say, ‘It’s like a race, the particles of water roll over each other very quickly, the particles in the oil do not roll over each other as quickly as the water one and the particles in the honey roll over each other very slowly.’
Later, when the children are working with this on their own give the new language; ‘Particles that roll over each other very quickly, like water are called ‘fluid’, the particles that roll do not roll over each other very quickly, like honey are called ‘viscous’ particles in the oil roll over each not as quickly as water, but more quickly than honey, like the oil, particles like this are called ‘fluid viscous’.
Aim:
Introduce finer discriminations to liquids, viscosity and fluidity.
Notes:
- We compare other liquids to water.
- Later, a second experiment can show that how, when heat is applied it increases the fluidity and decreases the viscosity of liquids.
Experiment 3
Rigidity of Solids
Material Description:
Seven bricks, one in a contrasting colour, the other six stacked in two columns of three, lengths of wood.
Method:
A
Begin with the supports quite close together and place the piece of wood over them. Place the contrasting coloured brick on the centre of the piece of wood, and comment that nothing happened, the wood is still rigid.
Place the bricks further apart, continue to comment on the rigidity and how the wood becomes more elastic.
B
Placing the brick closer to the supports, give the child the idea that this knowledge is important in the building of bridges and in engineering.
Aim:
A – Length reflects rigidity, a long body even though strong can become rigid under enough pressure.
B – where the weight is placed effects the bodies rigidity, the body is more rigid when the support is closer to the support.
Notes:
- Engineering, the effects of water, in nature, in events like the high jump and daily life experiences are brought together here.
- Rigidity is effected by length and pressure, where the force is applied and the thickness of the solid itself.
- In addition to, helping the children become more observant of their environment we are helping them to understand movements in the earth’s crust, while we usually think of the lithosphere as being solid it is flexible, we are also introducing, we are opening up basic mechanics, as a new field of exploration.
After the lesson:
If the children are interested, show examples with wood of difference thicknesses, different lengths of wood and different types of weights to compare the effects on rigidity.
Attraction of the Earth: Gravity
Experiment 1
Magnetism
Material Description:
Magnet, tray with a collection of objects magnetic and non- magnetic, e.g. nails, keys, clips, bolts, feather, blue-tac, stick, wax and piece stiff black paper
Method:
Place the objects on the paper one at a time and see if they are attracted towards the magnet, discuss the observations. Place the paperclips on in a line on the paper and show how the magnetic force passes through them.
Place the magnet under the paper, this demonstrates that the force works through the paper
Conclude:
This is like the force that exerts through everything on the earth, it has a special pull which stops us falling off. This special pull is called gravity, it’s name come from the Latin word ‘Gravis’ which means heavy.
Let a piece of paper of feather fall to the ground to show that even none-metallic objects are attracted to the ‘heart of the earth’
Experiment 2
Weight of liquids
Material Description:
Three test-tubes in a stand, each filled 3/4 full of water, water and honey, bung.
Method:
Refer to ‘The God with No Hands’ in which the dance of the elements is explained, in which the lighter particles floated above, like oil on water and the heavier particles sinking.
Pour the oil into the water and watch it float. Pour the honey through the oil and water and comment on how it sinks.
Explain how you will see if the positions of the liquids are always like this, place the bung on and invert it, say, ‘Liquids are so obliging that they let others pass through them, all because of the laws of gravity’.
Experiment 3
Wood and Weights
Material Description:
Thin strips of wood, six bricks to build the sides, another brick and weights with the quantity written. Set the bricks in towers at a distance and place the ends of the strip of wood on the bricks
Method:
Set the contrast brick at the centre of the wood and comment on it’s rigidity. Add more weights until the wood snaps. Say,’In solids the particles cling very closely together, but eventually they have to give way under the weight’, eventually the wood can no longer resist the pull of gravity.
Notes:
The quantity, written on the weights is an indirect preparation for measurement
Experiment 4
Movement also has an affect on gravity
Material Description:
Transparent bowl, full of course sand with small plastic containers with lids and plastic balls (especially ping pong balls) at beneath the sand, place heavy metal objects, bolts and magnets on the top of the sand
Method:
Say, ‘Let’s see what happens when we move the bowl’, and twist the bowl from side to side quickly, comment on how the heavy objects sink, while the lighter ones emerge and explain that, ‘This is due to the law of gravity, the heavier objects are immediately attracted towards the centre, or the heart of the earth, while the lighter ones move towards the top.’
Aim:
Here we give the law of gravity in isolation, in an impressionistic manner
When to give the lesson:
Some of these experiments can be given parallel to ‘Further States of Matter’, or shortly afterwards.
