atoms

atoms

1. protons have a relievant charge of +1

2. electrons have a relievant charge of -1

3. metals and non-metals

   • the metals shown on the left of the periodic table and the non metals on the left this is seperated by a red line

4. chemical symbols

   • the atoms of each element are repersented by a chemical symbol
   • usally consist of one or two letters even sometimes three for newly found elements

5. atomic structre

   • all substances are made from tiny paricles called atoms
   • an atom has a small central neclues mad up of sub-atomic particles called protons and neutrons
     • the nucleus is surronded by even smaller sub-atomic particles called electrons
     • protons and electrons have the same electrical charge but proton is positive and electron negative. neutrons are neutral

6. atomic number and mass number

   • The atomic number of an atom is the number of protons it contains. All the atoms of a particular element have the same atomic number (number of protons).
     • for example all oxygen atoms have 8 protons and all sodium 11 protons
   • The mass number of an atom is the total number of protons and neutrons it contains. The mass number of an atom is never smaller than the atomic number. It can be the same, but is usually bigger.

7. full chemical symbols

   • You need to be able to calculate the number of each sub-atomic particle in an atom if you are given its atomic number and its mass number. The full chemical symbol for an element shows its mass number at the top, and its atomic number at the bottom.
   • the number of protons and electrons in a atom are the same
   • you can work out the number of neutrons from the mass number and atomic number. for example 35 atomic number -17 mass number =18 neutrons

8. elctronic structre

9. elements

   • an element is somehting thats only made up of only one sort of atom
     • there are 100 different elements these are shown in the periodic table