Determine how mnay grams of CO2 are produced by burning 6.77 g of C4H10

Question

Determine how mnay grams of CO2 are produced by burning 6.77 g of C4H10

Answer 1

Hello, Kayla,

We need a balanced equation to start. This one is a little more challenging in that it requires large coefficients to properly balance. The basic reaction is:

C₄H₁₀ + O₂ = CO₂ + H₂O

We have 4 carbons for each reactant molecule, and this reacts with oxygen to form carbon dioxide and water. We therefore need to show 4 CO₂ molecules to consume these 4 carbons.

C₄H₁₀ + O₂ = 4CO₂ + H₂O

Next, let's balance the H atoms. The 10 H atoms from the C₄H₁₀ must fond a home in the water molecules. 5 water molecules can be made from 10 hydrogen atoms.

C₄H₁₀ + O₂ = 4CO₂ + 5H₂O

The only atom left is the oxygen. So far, the product side contains 13 O atoms (8 from the CO₂ and 5 from the H₂O). Awkward, since oxygen only comes in pairs, an even number. Let's use a fraction, 6.5, for the O₂ for now, just to get it balanced:

C₄H₁₀ + 6.5O₂ = 4CO₂ + 5H₂O

This equation is balanced, but not legal since we can't have 1/2 of an O₂ molecule. So simply multiply all coefficients by 2:

2C₄H₁₀ + 13O₂ = 8CO₂ + 10H₂O

The equation is now properly balanced. It is telling us that we'll get 8 moles of CO₂ for every 2 moles of C₄H₁₀. That's a molar ratio of 4CO₂/1 C₄H₈ .

Let's find the moles of C₄H₈ . Divide the grams C₄H₈ by it's molar mass (58.04g/mole).

6.77g/(58.04g/mole) = 0.1166 moles C₄H₈ .

Now multiply moles C₄H₈ by the molar ratio we calculated above:

(0.1166 moles C₄H₈ )*(4 moles CO₂/1 moles C₄H₈) = 0.467 moles CO₂

Convert to grams CO₂ by multiplying by CO₂'s molar mass:

(0.467 moles CO₂)*(44 g/mole CO₂) = 20.5 grams, to 3 sig figs

Bob