Name an example of chemical change?
Iron rusting, gas burning, eggs cooking, bread rising, something the can't be undone, something that makes a new substance.
What can happen in both a chemical and a physical change?
Change in state of matter.
What are the three main states of matter.
Solid, liquid, and gas.
What is the short hand way to say homogenous mixture?
Solution.
Melting a crayon is what type of change?
Physical change.
Name an example of a homogeneous mixture.
Salt water, lemonade, soda...
How can you tell something is a heterogenous mixture.
You can see the different part easily.
Scientific definition of matter.
Anything that takes up space and has mass.
What is the short hand way to say heterogenous mixture?
Mixture.
Burning a candle is what type of change?
Chemical change.
Trail mix, mixed nuts, a salad, a chocolate chip cookie...
How can you tell something is a homogenous mixture.
It looks the same throughout. It is difficult to see the different parts, or to separate the mixture.
Scientific definition of mass.
Sand and water mixed together is a...
heterogenous mixture. You can see different parts, not evenly mixed.
A construction company uses TNT to demolish a building, which causes the building to break and fall apart, crashing down to the ground.
Which was the physical change, which was the chemical change in the example above.
TNT exploding is a chemical change.
The building breaking apart was the physical change.
Anything on the periodic tables, such as gold, copper, zinc, oxygen.
List three pieces of evidence that a physical change has occurred.
Scientific definition of volume.
How much space an object takes up.
How can you separate a mixture of water and sugar?
Evaporate the water and the sugar will remain.
You make a sandwich with ingredients from your fridge, including lettuce, ham, and cheese, which you cut off a larger block. You slice the sandwich in two before eating it.
Which was the physical change, which was the chemical change in the example above?
Everything listed was a physical change. There has been no chemical change yet.
Name an example of a compound (A pure substance with TWO or more elements that cannot be separated without a chemical change.)
Water (H2O), Salt (NaCl), or Sugar (C12H22O11)
List three pieces of evidence that a chemical change has occurred.
Change in odor, change in color, change in temperature, gas or bubbles when not previously present, formation of a new substance, or creation of precipitate.
You cannot create or destroy matter, only rearrange the atoms.
Why can you separate mixtures but not compounds by physical means?
Because mixtures are physically combined, but compounds are chemically bonded.
When dropping mentos into a soda, the resulting reaction causes soda to spray up and out of the bottle.
Is this a physical or chemical change, and how do you know?
Physical change. The gas escaping the bottle is carbon dioxide, which was already present in the soda. No new substance has been created.