-Protons and neutrons both have equal masses. The total number of protons and neutrons in a atom is called the mass number.
- Atoms of the same element have the same atomic number.
Percentage and Formulae
-We can calculate the percentage of elements in a compound from the formula of the compound.
-How to work out the percentage of carbon in carbon dioxide-
(A of C = 12, A of O = 16)
M of CO2 = 12 + (16x2) = 44
So the percentage of carbon = (12/44) x 100 =27.3%
- If a product of a reaction is reversible then we use a symbol like this,
-Reversible reaction go in both directions as the symbol shows.
Making Ammonia- The Harbor Process
-The Haber process is used to manufacture Ammonia which can be used to make fertilizers and other chemicals.