# Guide to Stoich

## Type of Reaction : Combustion

To identify that it is a combustion, the reactant has to be O2 with anything else.

## Real Life Examples

Butane is founded in many fossils. One example would be putting gasoline into your car.

## How many moles of Carbon Dioxide can you make if you have 11.30 moles of Butane?

2. Look at coefficients, this will be your Stoichiometric Ratio. ( 2 to 8 or 8 to 2)
3. To cancel Butane out and find out how many Carbon Dioxide there are, put Butane on the bottom and Carbon Dioxide on top.
4. Multiply across the top and divide by the bottom.

11.30 moles of Butane | 8 moles of CO2 ----> (11.30 x 8)

---------------------------------------------------------- = -------------------- = 45.20 moles of CO2

~~~ (leave blank) ~~~~ | 2 moles of Butane

## If you have 7.04g of Butane, how many grams of Carbon Dioxide can be produced?

• 2. Use molar mass to find out how many moles are in 7.04g of Butane (MM=58.124g)
• 3. Look at coefficients, this will be your Stoichiometric Ratio. ( 2 to 8 or 8 to 2)
• 4. To cancel Butane out and find out how many Carbon Dioxide there are, put Butane on the bottom and Carbon Dioxide on top.
• 5. Use molar mass to find out how many grams are in those specific amount of moles. (MM=44.009g)
• 6. Multiply across the top and divide by the bottom.
• (7.04 x 1 x 8 x 44.009)

------------------------------- =21.3 g of CO2

(58.124 x 2 x 1)

## Limiting and Excess Reactants

Do mass and mass conversions of first reactant (Butane) with first product (CO2) and second reactant (Oxygen) with first product (CO2) also. The one with the least mass will be the Limiting Reactant (LR).

## Theoretical Yield

The theoretical yield is a number of grams (equal to the limiting reactant) of a substance or element that should be produced. In this case, the theoretical yield of Carbon Dioxide is 10.3 grams.