What is a Chemical Change? A chemical change is one where a new substance is formed. The change is often accompanied with other changes like a C_olour_________ change or T__emperature_________ change. Chemical changes are often difficult to reverse. Give an example: Cooking an egg What is a Physical Change? A physical change is one where no new substance formed. Physical changes are usually easy to reverse Give an example: freezing ice cubes
An element is made up of one type of atom A molecule is two or more atoms joined chemically together A mixture is two or more different substances mixed A compound is two or more elements joined chemically together
The periodic table is split in different ways: Groups Periods M_etals_______ and Non-Metals__________ Can you fill in the missing features of M’s and Non-M’s??
etals
Chemical Reactions with Acids Acid + Alkali ------> Salt + W_ater_______ Eg. Hydrochloric + Sodium-------> water Acid Hydroxide This is called a Neutralisation______ Reaction. Acid + Metal --------> Salt_____ + Hydrogen___ Eg. Sulphuric + Iron ----> Iron sulphate + hyrogen Acid Acid + Metal Carbonate-----> Salt_________ + Water___________ + C_arbon _________ D_ioxide_________ Eg. Nitric + Zinc ---------> Zinc Nitrate + water + CO2 Acid Carbonate
etals
olids
ases
lectricity lectricity
Chemical Reactions rittle alleable
pH Scale:
What 3 things do we need for combustion? What gas in the air reacts with metals when put in a flame?
Label the missing words
The name of the SALT comes from the M_etal_________ part e.g. sodium hydroxide would give a sodium salt. The name of the Acid____ indicates the second part of the name of the Salt_____.