Properties and Changes of Matter: Physical versus Chemical Changes Flashcards
1
Q
physical change
A
- alter a substance without changing its composition
- pounding an iron bar into a horseshoe
- tearing a piece of paper
- crushing rock salt
- changing state of matterq
2
Q
chemical changes
A
- a process that involves one or more substances changing into a new substance with new composition and new properties
- reactants - products
- burning gasoline in your car
- cooking pancake batter
- using an instant cold pack
- a banana rotting
- decompose, explode, rust, oxidize, corrode, tarnish, ferment, burn or rot
- mass of reactants = mass of products
- law of conservation of mass states that during a chemical reaction matter is neither created nor destroyed
3
Q
physical versus chemical changes
A
- physical and chemical changes, law of conservation of mass
4
Q
is the following a chemical or physical change?
Susbtance A and B are mixed, and heat is produced
A
- chemical
5
Q
is the following a chemical or physical change?
dry ice melts
A
- physical
6
Q
is the following a chemical or physical change?
water vapor condensing to form rain
A
- physical
7
Q
is the following a chemical or physical change?
burning wood to heat your house
A
- chemical
8
Q
is the following a chemical or physical change?
evaporation of water from a lake
A
- physical
9
Q
is the following a chemical or physical change?
hard-boiling an egg
A
- chemical
10
Q
is the following a chemical or physical change?
iron reacting with oxygen to form iron oxide
A
- chemical
11
Q
is the following a chemical or physical change?
dissolving salt in water
A
- physical
