Stoichiometry

[apchemstudent]

I have to define stoichiometry. Any one know a good definition for it? I'm reading a sentence it was used in "Many combinations of mono and trivalent cations yield crystals of the same stoichiometry and structure"

As well does anyone know a good definition of synthesis. Is it simply the combination of reactants to form a product?

thanks for your help.

[z-component]

Stoichiometry in the Merriam-Webster dictionary is definied as:

1 : a branch of chemistry that deals with the application of the laws of definite proportions and of the conservation of mass and energy to chemical activity
2 a : the quantitative relationship between constituents in a chemical substance b : the quantitative relationship between two or more substances especially in processes involving physical or chemical change

By synthesis I assume you mean a synthesis reaction. Correct me if I'm wrong on what you mean. But in chemistry, a general synthesis reaction is a reaction that follows the format of:

A +B \longrightarrow AB,

where A and B are reactants and AB is the product. A and B can be compounds or elements and AB is a compound.

Let me know if you need anything else.

z-component

[chem_tr]

Z-component has explained the issue pretty well, but I'll give some more details.

Let me give a real example to see what stoichiometry really is.

3Cu+8HNO_3 \longrightarrow 3Cu(NO_3)_2 + 2NO + 4H_2O

Stoichiometry is the method to find how many molecules will be in a reaction to give a full-balanced equation. This is my definition, and it fits here, I think.