How can I write synthesis reactions?
A synthesis reaction is is the combining of two single elements into a compound. This can be accomplished either as an ionic or molecular coupling in the pattern
We will look at two examples of synthesis, first the formation of Ammonia
To produce ammonia the basic equation is
We must remember that Nitrogen and Hydrogen are both diatomic molecules in their standard gas form. This adjusts the equation to
Now we need to adjust coefficients in order to balance the atoms on each side of the equation. Currently we have 2 atoms of nitrogen and 2 atoms of hydrogen on the reactant side and 1 atom of nitrogen and 3 atoms of hydrogen on the product side.
We can balance the hydrogens by placing a coefficient of 2 in front of ammonia and a coefficient of 3 in front of the hydrogen.
This gives us 6 hydrogen on each side and coincidentally the nitrogens now equal 2 on each side.
The equation is balanced.
In the case of the formation of Rust
The basic equation is
We are reminded that Oxygen is a diatomic and adjust the equation to
We now see 1 iron and 2 oxygen as reactants and 2 iron and 3 oxygen as products. We can balance the oxygen by placing a 2 coefficient in front of rust and a 3 coefficient in from of the oxygen to get 6 oxygen atoms on each side.
Since iron has only one atom on the reactant side we must use the coefficient 4 to balance the iron to 4 atoms on each side. To balance the final equation.
I hope this was helpful.