Chemical / Physical Changes Flashcards
Characteristics of a physical change
-No new products made
-Easily reserved
-Does not break or create new bonds between atoms
-Substance before and after are the same
Characteristics of a chemical change
-New products are made
-Chemical bonds are being created or destroyed
3 examples of a physical change
Breaking glass, Boiling water and Melting an ice cube
3 differences between a physical and chemical change
Physical change can be reversed, chemical change cannot.
Physical change produces new products, chemical change does.
Physical change does not break bonds and form new bonds, chemical change does.
3 examples of chemical change
Burning, Photosynthesis, Rusting
Difference between exothermic and endothermic reactions
Exothermic reaction releases energy, endothermic absorbs energy
5 ways to change the rate of a reaction (speed up or slow down)
Lower the temperature, Adding more reactants, Increasing surface area, Heating substances, Add a catalyst
5 observations that could provide evidence of a chemical change
-Precipitation appears in a liquid or gas
-Bubbles appear
-Change in colour
-Increase or decrease in temperature
-An odour is detected
What causes iron to rust
Iron reacts with Oxygen and Water
What occurs in a precipitation reaction
Two solutions are mixed and forms a cloudy mixture
Why photosynthesis is considered a chemical reaction
Components, or reactants, combine chemically at the molecular level to produce new substances.
What a catalyst is and explain whether it is a reactant, product or neither
Neither.
Exothermic & endothermic reaction examples
Exothermic: Combustion, Respiration & Iron rusting
Endothermic: Photosynthesis, evaporation & melting ice
