physical n' chemical change Flashcards
1
Q
defintion of physical change
A
a change in size, shape or state
2
Q
the 4 phase changes of a physical change
A
- melting
- evaporation
- condensation
- freezing
- sublimation
3
Q
definition of chemical change
A
a new substance is formed
4
Q
the 4 indicators of a chemical change
A
- change in color
- gas coming off ( fizzing or bubbling )
- change in temperature
- hotter = exothermic
- colder = endothermic - solid may be formed when 2 solutions are mixed together ( precipitate )
5
Q
how physical properties are different from chemical properties
A
physical properties : no new substance is formed, change can be seen in color, shape or state
chemical properties : happens on a MOLECULAR level, can’t see change bc a new substance is forming
6
Q
qualitative observations
A
observations using the 5 senses ( sense, smell, touch, taste, sound ), subjective
ex: the candle had a waxy surface after the fire died
7
Q
quantitative observations
A
observations using measurements, numbers + units
ex : the boiling temperature of water at sea level is 100°C
