Change Detectives

CHANGE DETECTIVES

THE MESS SCENE

SECTION ONEBY JACINTA M

• Physical change When something appears to be different• Chemical changeWhen something looks the same but the substance

changed• Reversible/ recoverableWhen something can be brought back to its original state • LiquidA wet substance that moves freely• SolidSomething hard that does not move freely• GasA boiling liquid form

Words you need to know

Our Change Detectives unit has been all about seeing how things, objects and substances change. Also we were investigating what reactions a liquid would have to a solid in a powder form. It was a lot of fun and it was very exciting to see an outcome that you wouldn’t expect. Now I will show you all of our investigations and results.

CHANGE DETECTIVES

The burning candle was a physical change because it appeared to be different. It wasn’t a chemical change because the wax remained the same, it just melted. It is partly a chemical change because the wick was burnt. The burning candle wasn’t recoverable because you can’t un-burn the wick.

THE BURNING CANDLE

We found that the icypoles didn’t take long to defrost. They changed because we left them in room temperature. The icypoles were recoverable because you can put in in the freezer and it will return to its original state. The icypoles was a physical change because they didn’t look the same.

ICYPOLES

The Berocca fizzing in the water was a chemical and a physical change. It was a chemical change because the substance inside changed. It was a physical change because the water turned red as soon as the Berocca tablet hit the water.

BEROCCA

The melted chocolate was recoverable because you can make it solid again by putting it back in the fridge. The melted chocolate is a physical change because it didn’t look the same from its original state

MELTED CHOCOLATE

The burnt chocolate was a chemical and a physical change because it didn’t look the same, (it didn’t smell the same either). The chocolate turned to ash because it was left in the microwave for too long.

BURNT CHOCOLATE

It’s not recoverable because you can’t bring the ash back to normal chocolate.

The vinegar on the table evaporated so it can not be recovered. It’s a physical and a chemical change, it was a physical change because it was no longer there so it looked different, a chemical change because the substance vanished so the substance changed.

VINEGAR

The frozen milk is reversible because you can change its stage by changing its temperature conditions. It’s a physical change because it looked icy and not as a liquid.

FROZEN MILK

The salt in the water is not reversible because once the salt is in the water and has dissolved you cannot separate it from the water. This experiment is a chemical change because you can’t see the salt once it has dissolved.

DISSOLVING SALT

What happened when you put the tartaric acid and bicarb soda in a glass was that it fizzed. If it didn’t have the acid in it, the substance wouldn’t of fizzed, that was what caused the reaction. It was chemical and a physical change because the substance changed and the water went foggy.

BICARB SODA AND TARTARIC ACID IN WATER

The perfume evaporated- like the vinegar so it couldn’t be reversed. It was both physical and chemical changes because it was no longer there it was completely different.

PERFUME

• Ice chunk• Observing tubes• Different stages of chocolate• Saturated salt• Berocca• Flame in a jar• Salvital in water• Bicarb soda and tartaric acid in

water

EXPERIMENTSSection two

• They proved that solids liquids and gasses can form into each other depending on different temperatures and conditions

• And that your predictions aren’t always accurate, experiments can surprise you

WHAT THE EXPERIMENTS PROVED

I learnt a lot in the science unit like all about solids liquids and gasses and how liquids react to powder solids. I also learnt what physical and chemical changes are.

WHAT I LEARNT