It only takes basic knowledge of the gas laws to know why this is.
Gas changes volume depending on temperature, and pressure. V- volume T- temperature k- constant Charles's law must be done in Kelvin because it is an direct variation.
Don't despair though all your hard work wasn't in vain just multiple by whatever makes that number a whole number Example: C3H7NO2 O2 -- CO2 H2O NO2 (1) (4.75) (3) (3.5) (1) As you can see not all the numbers came out as whole numbers, but it can easily be fixed by multiplying it by the least common multiple. C3H7NO2 O2 -- CO2 H2O NO2 (4) (19) (12) (14) (4) Always remember to check your work.
Once you get this down its on to the actual stoichiometry.
12/2=6 oxygen molecules That is the last number we need and the equation is balanced C6H12O6 O2 -- H2O CO2 (1) (6) (6) (6) That one was really easy but sometimes you will get an equation that doesn't work out so well.
Solve Stoichiometry Problems
Sometimes one of the number wont come out as a whole number and that just wont work, because you can't have half of a molecule.In simple words it states as pressure increases so does temperature. P- pressure T- temperature k- constant You can combine all three of those laws to get the combine gas law. To use this with stoichiometry you need to combine it with one last law, which is Avogadro's law.It states that at constant temperature and pressure equal volumes of gas contain the same number of moles.You can find the right amount to optimize the reaction and save reactants so you don't waste money. To help you understand how astronomically big this number is if I gave everyone on Earth (estimated 7 billion) million dollars a day; I could keep handing out money for 78564 years. For solids or liquids that aren't solutions its sample mass/molecular weight=moles. For example to find one mole of lets say carbon-14 the equation is x/14=1 x=14grams Another example: Find 5 moles of H2O. First off just pick a molecule(any of them work but the biggest is usually the best) and assign it a number (again any number works but to keep it easy use one).So far we have: C6H12O6 O2 -- H2O CO2 (1) So on the left side we have 6 carbon atoms 12 hydrogen atoms and an unknown amounts of oxygen atoms. Since we know the left sides number of carbon and hydrogen atoms we know the right sides number.I was looking around Instructables and saw many chemistry related Instructables, so I thought one on stoichiometry would help.Basically stoichiometry (my definition) is the study of amounts in relation to a chemical reaction.If you add up the mass for one side it should equal the sum of the mass on the other side.If not you messed up somewhere and need to review your work.You need a different mole equation to work with gases.Stoichiometry with gases everything stays the same but the equation you use to find the moles.