Science- Chemical and Physical Changes
oxygen reacted with the apple and turned it brown
A sliced apple left on the counter over night will turn brown. Explain the chemical reaction that took place.
Production of Precipitate
A solid substance that forms and separates from a solution.
Determine if a new substance with new properties has formed
How can you determine that a chemical change has occured?
add volume to the object
How can you make a dense material float?
Cold
Ice packs contain chemicals that become _______ when they react.
Oxidation- oxygen reacted with the apple
What caused the apple to change from white to brown?
When a substance rapidly combines with oxygen
What causes a combustion to occur?
light
What does burning wood or paper produce?
A flame that gives off thermal energy and light
What does combustion produce?
Chunky solid substance
What does the precipitate from combining milk and lemon juice look like?
thermal energy and light is produced and it glows
What happens when you agitate (shake) the chemicals in a glow stick?
Matter made of two or more types of atoms
What is a compound?
Matter made of a single type of atom
What is an element?
rusting; chemical
What occurs when a piece of iron or steel is exposed to water and oxygen over a period of time? Is it chemical or physical change?
baking soda and vinegar
What two common household items can you mix together to form a chemical change?
new substance or new property
What two things does a chemical change give off?
thermal energy and light
What two things does combustion give off?
Elements and Compounds
What two things from the passage can identify a specific type of matter?
Chemical- gas
What type of change causes the carbon dioxide to produce?
bubbles
When a GAS is produced in a REACTION involving a liquid, what is produced?
Physical Change
A change that involves changes to a substance's physical properties only.
Chemical Change
A change that involves changes to the physical and chemical properties of a substance.
Chemical Process
A process of chemical change happening
Physical Properties
A property that you can observe without changing the matter itself.
Chemical Properties
Different types of matter, including elements and compounds, have no different properties.
float
If an object is less dense, will it float or sink?
sink
If an object is more dense, will it float or sink?
chemical, physical, color, magnetic, electricity, density
List the 6 properties of matter: CPCMED
Color Change
The change in color, from white to brown. It provides evidence that a chemical reaction has happened.
Metals
What are dense because they have a great deal of matter packed into a small volume?
rusting, burning, exploding, rotting, bubbling
What are some examples of chemical changes?
chopping, melting, sanding, painting, folding
What are some examples of physical changes?
Physical property
This is a property you can observe without changing the matter itself.
Rust
This is a red flaky crust that crumbles easily. It can't change back to iron.
precipitate
This is a solid substance that forms and separates from a solution.
Production of Gas
This is produces in a reaction involving a liquid, bubbles form.
color change, light formation, gas bubbles, temperature change, precipitate
What are 5 evidences of Chemical change?
Production of Heat or Light
When a substance rapidly combines with oxygen, combustion occurs, producing a flame that gives off thermal energy and light.
The gas from the flame
When you burn a log, large amounts of heat is given off. What kind of evidence shows that it's a chemical change?
Carbon dioxide
When you combine baking soda and vinegar, the reaction that you see are bubbles of _____________ gas being produced.
a precipitate
When you combine lemon juice, milk, curdling occurs. What else forms?
react
When you freeze an ice pack, you cause the chemicals to connect to each other and _______
The very bottom
Where does a precipitate often settle in a liquid?
Chemical
Which change cannot be reversed? Physical or Chemical?
density
what is the amount of matter packed in a specific volume?
