Colour, Light and Heat

When you're out in the sun on a hot summers day it pays to wear some light colored clothes, but why is that? Experiment with light, color, heat and some water to find out.

What you'll need:

• 2 identical drinking glasses or jars
• Water
• Thermometer
• 2 elastic bands or some sellotape
• White paper
• Black paper

Instructions:

1. Wrap the white paper around one of the glasses using an elastic band or sellotape to hold it on.
2. Do the same with the black paper and the other glass.
3. Fill the glasses with the exact same amount of water.
4. Leave the glasses out in the sun for a couple of hours before returning to measure the temperature of the water in each.

What's happening?

Dark surfaces such as the black paper absorb more light and heat than the lighter ones such as the white paper. After measuring the temperatures of the water, the glass with the black paper around it should be hotter than the other. Lighter surfaces reflect more light, that's why people where lighter colored clothes in the summer, it keeps them cooler.

Blue, Yellow, Red, Green, Hot, Cold, Light, Dark?

Dissolving sugar in different heat

Learn about solutions as you add more and more sugar cubes to different temperature water. This easy experiment shows that you can only dissolve a certain amount and that this changes as the water gets hotter.

What you'll need: Sugar cubes Cold water in a clear glass Hot water in a clear glass (be careful with the hot water) Spoon for stirring Instructions: Make sure the glasses have an equal amount of water. Put a sugar cube into the cold water and stir with the spoon until the sugar disappears. Repeat this process (remembering to count the amount of sugar cubes you put into the water) until the sugar stops dissolving, you are at this point when sugar starts to gather on the bottom of the glass rather than dissolving. Write down how many sugar cubes you could dissolve in the cold water. Repeat the same process for the hot water, compare the number of sugar cubes dissolved in each liquid, which dissolved more? What's happening? The cold water isn't able to dissolve as much sugar as the hot water, but why? Another name for the liquids inside the cups is a 'solution', when this solution can no longer dissolve sugar it becomes a 'saturated solution', this means that sugar starts forming on the bottom of the cup. The reason the hot water dissolves more is because it has faster moving molecules which are spread further apart than the molecules in the cold water. With bigger gaps between the molecules in the hot water, more sugar molecules can fit in between. Brrr, Brrr, Hot, Hot?

Does an Orange float or sink?

Does an orange float or sink when placed in water? Seems like a fairly straight forward question, but is it? Give this fun density science experiment for kids a try and answer the question while learning a unique characteristic of oranges.

What you'll need:

• An orange
• A deep bowl or container
• Water

Instructions:

1. Fill the bowl with water.
2. Put the orange in the water and watch what happens.
3. Peel the rind from the orange and try the experiment again, what happens this time?

What's happening?

The first time you put the orange in the bowl of water it probably floated on the surface, after you removed the rind however, it probably sunk to the bottom, why?

The rind of an orange is full of tiny air pockets which help give it a lower density than water, making it float to the surface. Removing the rind (and all the air pockets) from the orange increases its density higher than that of water, making it sink.

Density is the mass of an object relative to its volume. Objects with a lot of matter in a certain volume have a high density, while objects with a small amount of matter in the same volume have a low density.

Blup, Blup, drowning, drowning

Stab a Potato using a Straw

Is it possible to stab a potato with a drinking straw? Find out with this fun science experiment for kids that shows how air pressure can be used in surprising ways.

What you'll need:

• Stiff plastic drinking straws
• A raw potato

Instructions:

1. Hold a plastic drinking straw by it sides (without covering the hole at the top) and try quickly stabbing the potato, what happens?
2. Repeat the experiment with a new straw but this time place your thumb over the top, covering the hole.

What's happening?

Placing your thumb over the hole at the top of the straw improves your ability to pierce the potato skin and push the straw deep into the potato. The first time you tried the experiment you may have only pierced the potato a small amount, so why are you more successful on the second attempt?

Covering the top of the straw with your thumb traps the air inside, forcing it to compress as you stab the straw through the potato skin. This makes the straw strong enough to pierce the potato, unlike the first attempt where the air is pushed out of the straw.

Uuuuu, great!

Static Electricity

They say opposites attract and that couldn't be truer with these fun static electricity experiments. Find out about positively and negatively charged particles using a few basic items, can you control if they will be attracted or unattracted to each other?

What you'll need:

• 2 inflated balloons with string attached
• Your hair
• Aluminium can
• Woolen fabric

Instructions:

1. Rub the 2 balloons one by one against the woolen fabric, then try moving the balloons together, do they want to or are they unattracted to each other?
2. Rub 1 of the balloons back and forth on your hair then slowly it pull it away, ask someone nearby what they can see or if there's nobody else around try looking in a mirror.
3. Put the aluminium can on its side on a table, after rubbing the balloon on your hair again hold the balloon close to the can and watch as it rolls towards it, slowly move the balloon away from the can and it will follow.

What's happening?

Rubbing the balloons against the woolen fabric or your hair creates static electricity. This involves negatively charged particles (electrons) jumping to positively charged objects. When you rub the balloons against your hair or the fabric they become negatively charged, they have taken some of the electrons from the hair/fabric and left them positively charged.

They say opposites attract and that is certainly the case in these experiments, your positively charged hair is attracted to the negatively charged balloon and starts to rise up to meet it. This is similar to the aluminium can which is drawn to the negatively charged balloon as the area near it becomes positively charged, once again opposites attract.

In the first experiment both the balloons were negatively charged after rubbing them against the woolen fabric, because of this they were unattracted to each other.

BZZZZZ, BZZZZZ, BZZZZZ, BZZZZ, an electric shock

Making a Parachute

This is Cathy and me, we were making a parachute. Mr. Anjar took a picture of us.

REFLECTION:
I like to make a parachute, but it is hard, that day I don't finished the parachute yet, so, I bring it home, but, I can't make it at home. I bring the things I need to school and I make it at school, I make it easily, not like at the class, I make it at the playground, when it's home time. I want to make it again but, I don't have the things anymore, Hahahaha

Breeding Bacteria

Bacteria are a fascinating type of microorganism that play a large role in our lives whether we like it or not. Try growing your own sample of bacteria while monitoring how it reproduces in a short space of time. Compare your original sample with others and get proof that bacteria truly are everywhere!

What you'll need:

• Petrie dish of agar
• Cotton buds
• Some old newspaper (to wrap petrie dish when disposing)

Instructions:

1. Prepare your petrie dish of agar.
2. Using your cotton bud, swab a certain area of your house (i.e. collect a sample by rubbing the cotton bud on a surface of your choice).
3. Rub the swab over the agar with a few gentle strokes before putting the lid back on and sealing the petrie dish.
4. Allow the dish to sit in a warm area for 2 or 3 days.
5. Check the growth of the bacteria each day by making an observational drawing and describing the changes.
6. Try repeating the process with a new petrie dish and swab from under your finger nails or between your toes.
7. Dispose of the bacteria by wrapping up the petrie dish in old newspaper and placing in the rubbish (don't open the lid).

What's happening?

The agar plate and warm conditions provide the ideal place for bacteria to grow. The microorganisms on the plate will grow into individual colonies, each a clone of the original. The bacteria you obtained with the cotton bud grows steadily, becoming visible with the naked eye in a relatively short time. Different samples produce different results, what happened when you took a swab sample from your own body?

You will find bacteria throughout the Earth, it grows in soil, radioactive waste, water, on plants and even animals too (humans included). Thankfully for us, our immune system usually does a great job of making bacteria harmless.

MORE BACTERIA on the house