Atoms & Compounds

Atoms & Compounds

1. Atomic Number

   • Number of protons

2. Mass number

   • Total of protons and neutrons

3. Atoms of the same element all have the same number of protons

   • So atoms of different elements will have different number of protons

4. How to get the number of neutrons?

   • subtract the atomic number from the mass number

5. Relative mass is very small

6. Compounds

   • Chemically bonded
   • Compounds are formed when atoms of two or more elements are chemically combined together.
   • Eg. C + 02 = CO2