Chemical vs. Physical Changes
Pranav R. & Dillon P.
Chemical Changes
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).
Physical Changes
Physical changes are changes affecting the form of a chemical substance, but not its chemical composition. Physical changes are used to separate mixtures into their component compounds, but can not usually be used to separate compounds into chemical elements or simpler compounds.
Rusting Nails
Cutting Vegetables
Burning Wood
Practice Quiz: Chemical vs. Physical Changes
State if the following is a physical or chemical change:
1.Sodium Hydroxie dissolves in water
2.Water is heated and changed to steam
3.Iron rusts
4.Evaporation
5.Ice melting
6.Milk sours
7.Sugar dissolves in Water
8.Wood rotting
9.Pancakes cooking on a griddle
10.Grass growing in a lawn
11.A tire is inflated with air
12.Food is digested in the stomach
13.Water is absorbed by a paper towel
14.An iron scorches a shirt when you leave it on one spot too long
15.The tires on your car seem to be getting low in very cold weather
16.Your grandmothers silver tea set gets black with tarnish over time
17.Spray-on oven cleaner converts grease in the oven into a soapy material
18.An ordinary flashlight battery begins to leak with age and cant be recharged
19.Acids produced by bacteria in plaque cause teeth to decay
20.Sugar chars if overheated while making homemade candy
21.Hydrogen peroxide fizzes when applied to a wound
22.Dry ice evaporates without melting as time passes
23.Iron metal is melted
24.Wood burns in a fire
25.A rock is broken into small pieces
26.Wax is melted over a flame and then catches fire and burns
Answers to Quiz
Answers:
1.Physical
2.Physical
3.Chemical
4.Physical
5.Physical
6.Chemical
7.Physical
8.Chemical
9.Chemical
10.Chemical
11.Physical
12.Chemical
13.Physical
14.Chemical
15.Physical
16.Chemical
17.Chemical
18.Chemical
19.Chemical
20.Chemical
21.Chemical
22.Physical
23.Physical
24.Chemical
25.Physical
26.Chemical