A Guide to Stoichiometry:
using baking soda and hydrochloric acid
Let's Get to Know Baking Soda and Hydrochloric Acid
Type of Reaction:
Double Replacement
Balanced Equation:
IUPAC names:
Baking soda: Sodium Hydrogen Carbonate
HCl: Hydrochloric Acid
NaCl: Sodium Chloride
Water: Dihydrogen Monoxide
CO2: Carbon Dioxide
Uses:
- Cooking purposes
- Fighting Fires
Baking Soda and Hydrochloric Acid
Molar Mass
- Needed for later conversions
- To do, add all the element's atomic mass together, making sure to multiply each element's mass with its subscript
Baking soda:
(22.990) + (1.008) + (12.011) +3(15.9994) = 84.006 g
Na + H + C + 3(O)
Hydrochloric Acid:
(1.008) + (35.453) = 36.461 g
H + Cl
Salt:
(22.990) + (35.453) = 58.443 g
Na + Cl
Water:
2(1.008) + (15.9994) = 18.015 g
2(H) + O
Carbon Dioxide:
(12.011) + 2(15.9994) = 44.009 g
C + 2(O)
Mole to Mole Conversion
- The first mole A is your given.
- Mole B over Mole A is the coefficients of your balanced formula
- Multiply the top, divide by the bottom and you get your answer!
- Don't forget units! And Sig Figs!
Let's try an example!
Mass to Mass Conversion
- The first grams A is your given.
- The second grams A is your molar mass (refer to the top section) of your atom in one mole of that atom
- Mole B over Mole A is the coefficient from the balanced equation
- Grams B over Mole B is the molar mass of your other atom in one mole
- Multiply the top, divide by the bottom and you get your answer!
- Don't forget units! And Sig Figs!
Let's try an example!
Limiting and excess reactant
- Use mass to mass conversion to find out how many mass of a product can be produced with a specific amount of the reactants
- Convert your first reactant to a specific product and do the same for the other reactants
- The reactant that makes the least product is your Limiting Reactant (LR) and the reactant that makes the most product is your Excess Reactant (ER)
- Don't forget units! And Sig Figs!
Let's try an example!
This states that baking soda is the LR and the hydrochloric acid is the ER!
Theoretical Yield
- The amount of product you predict to come out from your experiment if everything is done perfectly
- Found by the mass to mass conversion of the LR
For baking soda and hydrochloric acid, the theoretical yield is...
Percent Yield
- A percent that states how close your experiment was to what was supposed to come as a result
Let's say the experiment came out with 2.52 g of carbon dioxide, let's see what's the percent yield
You were pretty successful in your experiment!
- It is hardly ever 100% yield since there are small errors that could happen that alter the results
For More Info....
Stoichiometry: Chemistry for Massive Creatures - Crash Course Chemistry #6