Tag: Science

• Conduction is when heat moves through a solid, heating up and placing more energy into the particles, making them bump and vibrate together, transferring their thermal energy to the other particles around them.
• Convection is when heat moves in liquids and gases as warm particles with more thermal energy will rise and cool particles with less thermal energy will sink. Convection occurs due to the particles with more thermal energy pushing one another away, making the liquid or gas less dense as there are larger spaces between the particles.

  Warm Molecules, and Cool Molecules

• Expansion + Contraction, when particles vibrate faster and push each other apart when thermal energy is added, causing solids, liquids, and gases to expand. Contraction is when that energy is removed, causing the states to shrink and contract into a smaller shape.

All particles in a solid vibrate – even when cold.

At higher temperatures, they vibrate faster and take up more room – expand – but the particles themselves are still the same size.

• Diffusion is when particles spread from an area where there are too many to where there are fewer. Diffusion happens because particles bounce around and push one another away. Gases diffuse to fill their container entirely, but solids won’t diffuse unless something breaks the bonds that hold the particles together, for example, salt dissolving in water.

High concentration, Movement of particles, Low concentration.

• Conduction (Dropping pins experiment)
• Convection (Water experiment)
• Expansion + Contraction (Crushed can experiment)
• Diffusion (Petri dish experiment)

When doing experiments around these four things about particles, we were exploring the effects of heat.

But in the end, I quite enjoyed the Expansion + Contraction experiment. This experiment aimed to observe how, when hotness is rapidly turned into cold, a lot of pressure builds up, causing the container or can to crush. In this experiment, my hypothesis was that it would take only seconds for the can to crush due to the high pressure.

Step-by-step method for this experiment.

1. Set up a Bunsen burner under a tripod and a gauze mat after lighting it.
2.  Pour about two teaspoons into the can.
3.  Heat the can until steam comes out of the top of the can (Placing it on the gauze mat)
4.  Once heated, grip the top of the can with scissor tongs, and carefully lift it above the container that is filled with water.
5.  Quickly flip the opening of the can into the water.

What I observed/ saw.

• Steam coming out of the top of the can opening
• The sound of the water boiling in the can. 
• When I removed the can from the heat and quickly flipped the opening into the water, it crumpled up due to the pressure from the different temperatures.

In the end, the discussion was:

As steam, the water particles inside the can turn into a gas when heat from the Bunsen burner is added. The gas fills the space in the can, and as the particles bounce off the container, some float up and out of the opening if it is not closed. When the can is suddenly flipped into cold water, the gas inside quickly cools and turns back into liquid water. This leaves less gas inside the can, so the air pressure outside the can becomes much greater than the pressure inside, and this difference in air pressure crushes the can.

With a lot of talking, here is my write-up after the experiment.

Expansion + Contraction experiment write-up link

Diffusion Experiment

The equipment we used was:

• 2 Petri dishes
• Hot water, and cold water
• Tweezers

The step-by-step method for my experiment is as follows:

1.  Fill half of your petri dish with cold water.
2.  Place the petri dish on your workbench to allow the water to settle
3.  Using the tweezers, place a single potassium permanganate in the center of the dish.
4.  How long does it take for the water to become purple using a device
5.  Repeat steps with hot water.

I also liked this experment so I shall give you a quick summary over it all.

The aim was to observe how potassuim paermananate diffuses in hot versus cold water. A crystal was place in the center of each petri dish filled with hot and cold water, after that we timed how long it took for the each of the water to turn purple.

The results showed that the crystal diffused faster in hot water (about 8 min 43 sec) than in cold water (about 10 min 12 sec). The discussion explais tis using particle theory: hot water has more energy, so particles move more quickly from an area of high concentration to low concentration, causeing faster diffusion.

The write up also says ways to improve accuracy, such as using the same size container and the same amout of water. The conclusion is that the results support the idea of particles move quicker in warm conditions.

Diffusion write up link

27/02/26

Scientific Method:

1. Title:
2. Aim: What you are trying to find out by doing the investigation.
3. Method: Steps that detail what you will do – can be repeated by others.
4. Results: Recorded observation or measurements – often in a table.
5. Analysis: Calculations, graph, or findings.
6. Discussion: Science ideas to explain your results, possible improvements to the investigation.
7. Conclusion: What your results tell you – linked back to the aim.

In this experiment, we are exploring conduction.

(Conduction: Particles in a solid vibrate and transfer some of their thermal energy to nearby particles. Some materials conduct heat better than others. Metals transfer thermal energy between their particles rapidly, while insulators like plastic do so slowly.)

We set up a ring holder and attached an aluminum rod to it with stuck pins with vaseline. We set a Bunsen Burner and lit it, to place under. By using a stopwatch, we measured the distance of the pins, and how long it took for the first pin to fall.

(Sorry if it isn’t clear.)

THANK YOU SO MUCH BAIII

In science, we did an experiment to see what happens when we heat ice. We put 250 ml of ice into a beaker and heated it with a Bunsen burner. We measured the temperature every minute. At 1 minute, it was 5°C and then went up as the ice was given more and more energy. The ice started to melt at about 38°C and slowly turned into liquid water. After all the ice had melted, the water continued to heat until it reached about 103°C. This shows how states and particles change when energy is added and removed. Today, we had to gather the information and put the times and temperatures into a graph and answer the questions below it. In the graph, after placing crosses that show what the time was when it was this temperature. We found the line of best fit and then added a title.

That’s it.

States of matter

We had to write about the things we have learned, along with their concepts and explanations.

1. Solid – Matter that keeps its shape and has a fixed volume, like ice or a rock.
2. Liquid – Matter that flows and takes the shape of its container, like water.
3. Gas – Matter that spreads out to fill any space, like the air we breathe.
4. Plasma – A very hot state where atoms are broken into charged parts, found in stars and lightning.
5. Melting – When a solid changes into a liquid by heating, like ice turning to water.
6. Freezing – When a liquid turns into a solid by cooling, like water turning into ice.
7. Evaporation – When a liquid changes into a gas, like puddles drying up in the sun.
8. Condensation – When a gas cools and turns back into a liquid, like water drops forming on a cold window.
9. Sublimation – When a solid changes straight into a gas without becoming a liquid first, like dry ice disappearing.
10. Deposition – When a gas changes directly into a solid without becoming a liquid, like frost forming on leaves.