What is the difference between Chemical Changes/Properties and Physical Changes/Properties? I need 15 examples of each.Things that you can experience in a 24 hour period. Examples of Chemical...
What is the difference between Chemical Changes/Properties and Physical Changes/Properties? I need 15 examples of each.
Things that you can experience in a 24 hour period. Examples of Chemical Changes/Properties and Physical Changes/Properties.
hye saul your question is so nice
There are two possible definitions for Physical and Chemical changes which I use in school:
1. A physical change is reversible, a chemical change is not.
2. A physical change is a change in which no new substance is formed; a chemical change results in the formation of one or more new substances.
you need 15 examples of both so here goes
Any change in the physical properties of an object without altering the chemical makeup of it.
- water freezing (ice)
- ice melting
- cutting a tree down
- shaping of raw materials into products
- 11.cutting carrots
13.dissolving sugar in water
14.using salt to melt ice
16.grinding meat to make hamburger
17.frost forming on the window
18.fog forming at night
A usually irreversible change in the arrangement of atoms in an object.
- combustion (burning)
- ripening (i.e. fruits and vegetables)
- consuming food
- various biological processes (i.e. photosynthesis)
- 11.baking a cake
13.a nail rusting
14.silver spoon tarnishing
15.lighting a match
17.using a battery (turning on a flashlight)
18.frying an egg
19.a cheap ring on your finger making it turn green
20.mixing vinegar with baking soda
Chemical change is any change that results in the formation of new chemical substances. At the molecular level, chemical change involves making or breaking of bonds between atoms. These changes are chemical:
- iron rusting (iron oxide forms)
- gasoline burning (water vapor and carbon dioxide form)
- eggs cooking (fluid protein molecules uncoil and crosslink to form a network)
- bread rising (yeast converts carbohydrates into carbon dioxide gas)
- milk souring (sour-tasting lactic acid is produced)
- suntanning (vitamin D and melanin is produced)
Physical change rearranges molecules but doesn't affect their internal structures. Some examples of physical change are:
- whipping egg whites (air is forced into the fluid, but no new substance is produced)
- magnetizing a compass needle (there is realignment of groups ("domains") of iron atoms, but no real change within the iron atoms themselves).
- boiling water (water molecules are forced away from each other when the liquid changes to vapor, but the molecules are still H2O.)
- dissolving sugar in water (sugar molecules are dispersed within the water, but the individual sugar molecules are unchanged.)
- dicing potatoes (cutting usually separates molecules without changing them.)