Category Archives: Science

Volcanic eruption

Today Robins watched what a volcanic eruption would be like… well we tried!

Using Ammonium Dichromate we tried to simulate a volcanic eruption.

By heating the bottom of the conical flask we simulated the heat built up inside a volcano. Usually when the Ammonium heats it flares giving a green gas as it ignites. The green gas is nitrogen and can be smelly, but we had glass wool plugging the top of the flask.

We did see some sparks and the chemical reaction did create a lot of smoke in the flask. Unfortunately because the Ammonium did not stay as one lump (it spread out a bit too thinly) it did not create a hugely exciting reaction.
Hopefully the next class to do it will get a better result and we can watch their attempt!

The chemical reaction left the Ammonium Dichromate as charred ash, just as you would see in a volcanic eruption.

We learnt that not all experiments will work first time, and that it is important to watch carefully as some chemical reactions are super fast. We did enjoy it though. It was a little bit like watching miniature fireworks in the flask! Another exciting science lesson in Robins class!

Ice-cream in a bag!

In Science, Year 4 Robins have been making their very own ice-cream. They have asked if we can put the instructions on the blog so that they can try it again at home!

What you will need:
• Small bag
• Large bag
• Milk
• Caster sugar
• Ice
• Salt
• Vanilla essence
• Spoon
• Plastic tub

How to make the ice-cream:
1. Crush the ice cubes.

2. Pour 150ml of milk into the small bag and mix with a tablespoon of sugar and a few drops of vanilla essence. Seal the bag properly.

3. Place the small bag inside the large bag and fill it with ice so that the milk is covered.

4. Add 6 tablespoons of salt to the ice and make sure you seal the second bag properly as well.

5. Massage and shake the bag for approximately 5 minutes until your mixture has turned into ice-cream. Your fingers are going to get really cold!

6.Put the ice-cream into the tub, grab your spoon and enjoy!

Effective solvents

This afternoon Robins put on their safety goggles and gloves to complete an investigation.
They were investigating which solvents were the most effective at removing nail varnish.
They had the following solvents:

  • Water
  • Hydrochloric acid
  • Ethanol
  • Propanane
  • Bleach
  • Before the investigation, they predicted which one they thought would be th most effective. Which one would you have chosen?

    Each pair were given a tile and the painted 5 lines of nail varnish on them.
    Then with a cotton bud dipped into one of the solvents, they tried to remove the varnish.
    They then recorded their results. Have a look at what they found.

    Video: Kinetic energy

    Robins were experimenting with air today.

    They use an airzookla, which is a gadget that shoots out puffs of air. Miss Edwards shot out puffs to knock down cups off the table.

    When she pulled back the tab on the airzookla, it sucked in some air and as she released the tab, it shot the air out!

    To show it better, we used a smoke machine….

    We could then easily see how the airzookla created kinetic energy which made the smoke travel. It then began to lose kinetic energy as it travelled through air. The smoke began to dissolve as it travelled because it mixed with air particles.

    Investigating salt and sugar

    Year 4 have continued their science learning and have been investigating the solubility of salt and sugar.

    The children worked in pairs to put salt and sugar into cold water and see which dissolved the quickest.

    The children ended up having a real mixture of results therefore we discussed the reliability of the experiment. The children discussed how it wasn’t really a fair test because you could have accidentally put more sugar in the water than salt.

    Year 4 have learnt that science doesn’t always go to plan but that’s part of the fun!

    Mentos sweet experiment

    Year 4 discussed what they thought would happen when Mentos sweets were dropped into a bottle of Cola.

    Lots of children thought the Mentos would dissolve. The class walked onto the field to watch the experiment. Can you predict what happened?

    As soon as the Mentos touched the Cola there was a huge explosion of Cola! The brown bubbles flew high into the air. It was very exciting to watch.

    The children used some good language to describe what they saw:
    Explosion
    Eruption
    Fizzing
    Volcano
    Dissolve
    Collide
    Melt

    Well done Robins.