chapter 11 Flashcards
1
Q
physical change
A
- no new substance formed
- easily reversed
- change of state
2
Q
chemical change
A
- new substance formed
- not easily reserved
- substances react to form new substance
- substance becomes 2 substances
3
Q
how to identify chemical change
A
- gas is produced
- change in colour
- change in temperature
- precipitate is formed
4
Q
types of chemical change
A
- combustion
- oxidation
- decomposition
- neutralisation
5
Q
combustion
A
- substance reacts with oxygen when heated to form one or more new substances
- heat and light can be given out
6
Q
oxidation
A
- addition of oxygen to a substance
- occurs when other elements, metal, not metals burn in air
7
Q
oxidation example
A
iron combine with oxygen in air to form new substance: rust
8
Q
oxidation and combustion example
A
- burn magneisum in air, new subtance, magnesium oxide is formed
9
Q
neutralisation
A
reaction between acid and akalis, forming salt and water
10
Q
acids
A
produce hydrogen when dissolved in water
11
Q
alkalis
A
produce hydroxide when dissolved in water
12
Q
acid + alkali
A
- salt and water
13
Q
acid + metal
A
- salt + hydrogen
14
Q
how to test for hydrogen
A
- place lighted splint near gas and it should extinguish with a pop
- hydrogen is very flammable
15
Q
acid + carbonate
A
- salt water carbon dioxide
