Chemistry Friends/Quantitative Relationships in Chemical Changes

In quantitative relationships, you can use a balanced chemical equation and knowledge about how much of a substance there is to find out what substance you will have too much of, what you will run out of and how much of a substance you will need. Limiting Reagent is the substance that runs out, and excess reagent is the substance you have leftovers of.

Gravimetric Stoichimetry


Gavemeter is determining solid reactants by weight.

Gas Stoichimetry


When using gas stoichmetry determine the amount of gas used by volume. The STP (standard temperature and pressure) is 22.4 L/mol. The SATP (standard ambient temperature and pressure) is 24.8 L/mol. A formula you can use with gas stochimetry is pv=nRT. 'p' is pressure, 'v' is volume, n is moles (not moler mass) 'R' is the constant (8.31 kPa×L/mol × Kalvin) and 'T' is the temperature in Kalvin. You use this formula to find any one of the reactants.

Chemical Analysis By Titration(Solution Stoichimetry)


Titration is determining liquid reactants by mol/L. In titration, we know the concentration of one the reactants. One way of finding the concentration of one of the reactants is by adding the reactant with the known concentration to the reactant with the unknown concentration a little bit at a time using a buret. When the reactant with the unknown concentration fully reacts with the other reactant, you can check the buret to see how much known reactant you used. then look at the balanced chemical equation to calculate the concentration of the reactant.