Physical Changes
What does it mean to go through a physical change?
No new substances are made. It can go back to its original form.
What does it mean to go through a chemical change?
New substances are made. It can't go back to its original form.
What is a mixture?
When two substances mix physically but does not mix chemically like sand and water.
What is a solution?
When two substances mix physically and chemically like sugar and water.
What is another term for physical changes?
Reversible change.
What is another term for chemical changes?
Irreversible change.
Give an example of a mixture other than sand and water.
Give an example of a solution other than sugar and water.
Milo, instant coffee, etc.
True or false: Baking bread is a physical change.
False
True or false: Baking bread is a chemical change.
True
True or false: Cereal and milk is a mixture.
True because they are not chemically mixed, just physically.
True or false: Fizzy drinks are solutions.
True because carbon dioxide is dissolved in water.
Give an example of physical change other than water.
Chopping wood, cutting paper
Give an example of chemical change other than cooking or baking.
Fire burning, rusting metal
True or false: Mixing tomato sauce and BBQ sauce is a solution.
False because sauces are thick and have different ingredients that don't completely dissolve into each other.
True or false: Mixing tomato sauce and BBQ sauce is a mixture.
True because sauces are thick and have different ingredients that don't completely dissolve into each other.
Why is boiling water a physical change?
Because the water that you boil can evaporate into gas and that gas can cool down back into liquid, going back to its original form.
Why is digesting food in your stomach a chemical change?
Because your stomach acid is breaking down the food you ate so your body can absorb it easily. You also cannot undigest food.
Why is mayonnaise a mixture?
Because it is a mixture of oil, egg yolk, and vinegar.
Why is hand sanitiser a solution?
Because alcohol is dissolved in liquid.