Number of protons, neutrons and electrons

• The atomic number (The smaller number) tells us how many protons and electrons are present in an element
• The mass number is always the bigger number.
• Neutrons= Mass number-The atomic number
• The number of neutrons in carbon is equal to 12-6=6

  
• Compounds contain 2 or more elements chemically combined together in a fixed proportion.
• Elements contain only 1 type of atom
• To seperate a compound back into its elements you must use a chemical reaction to do this
• In a mixture, we have different elements or compounds but they are not chemically combined together
• To separate a mixture you have to use a physical method
• A molecule has any elements chemically joined