Chemistry

Stoichiometry of the chemical equation


Stoichiometric calculations involving a chemical reaction consist of finding the quantities of certain substances from data of other substances participating in the same chemical reaction.

These calculations are made by proportions. We must take into account the coefficients, which will now be called stoichiometric coefficients.

Here are some steps you can take to assemble and calculate:

1. Balancing the chemical equation (adjusting the stoichiometric coefficients);
2. make mol count of each substance;
3. read in the problem what is requested;
4. relate the quantities;
5. calculate with rule of three (proportion).

Examples:

1) 108g of aluminum metal react with sulfuric acid, producing salt and hydrogen, according to the reaction below:

Determine:

a) balancing the equation:

  

This means that 2 mol Al reacts with 3 mol H2ONLY4 reacting with 1 mol Al2(ONLY4)3 and 3 mol of H2

(b) the mass of sulfuric acid required to react with aluminum:

1st) step: 2nd) step:
           
                                         
                         
3rd) step:

x = 588g of H2ONLY4

Relate the acid mass to the aluminum mass as in step 3. Rather, in step 1 and step 2, turn the number of moles to grams.