Starting with 55.2 g of acetylene find the theoretical yield in grams of CO2

Question

2H-C=CH (g) + 5 O2(g) —> 4 CO2 (g) + 2H2O

Starting with 55.2 g of acetylene find the theoretical yield in grams of CO2 (molar mass C2H =26.04g/mol; molar mass of CO2 = 44.02)

What is the yield of carbon dioxide gas in liter ?assume standard temperature and pressure for the gas

Answer 1

Hi Iris,

We always want to start problems with reactions with balanced chemical reactions. The given reaction is balanced so we're good to go.

Next, we want to convert everything to moles, since that will be the easiest way to get from one molecule to another in a chemical reaction.

We are given a known quantity of acetylene (C2H2) as 55.2g and given the molecular mass of this compound (26.04 g/mol). Therefore we can find the moles of C2H2 that is present.

Afterwards, we want the theoretical yield of CO2. As mentioned earlier, we would want to find the moles in order to go from one molecule to another. With the moles of C2H2 from the previous section, we can now convert moles C2H2 -> moles CO2 using the fact that for every 2 moles of C2H2, 4 moles of CO2 are formed via the balanced chemical reaction.

We now have moles of CO2. Using the molar mass of CO2, we now have the mass of CO2.

In order to find the liters of CO2, we can use PV = nRT and solve for V in liters.

Hope this helps!

-Winn