chemical changes Flashcards
1
Q
What is combustion?
A
A chemical reaction in which a substance is heated in the presence of oxygen to form one or more new substances
Heat and light is usually given out
2
Q
define neutralisation
A
The reaction when an acid reacts with an alkali, to form Salt and Water
3
Q
what is an alkali?
A
a chemical that can dissolve in water
4
Q
what is an acid?
A
a substance which contains hydrogen and can react with other substances to form salts
5
Q
define oxidation
A
a chemical change when a substance gains oxygen
**from OXIdation
OXYGEN
6
Q
define thermal decomposition
A
the process in which a substance breaks down into two or more simpler substances upon heating
which forms the word equations
7
Q
what is the pH level of acids?
A
pH1-6
8
Q
what is the pH of alkalis?
A
pH8-14
