# Working with balanced chemical equations

(any number following an asterisk is a subscript)

Using the equation for the combustion of methane:

CH*4(L) + O*2(G) --> CO*2(G) + H*2O(G) answer the following:

A. Is the equation properly balanced and if not balance it.

B. Name the compounds in this reaction.

c. How many moles of O*2 react with 1 mol of CH*4?

D. How many grams of O*2 react with the 1 mol of CH*4?

E. How many grams of CO*2 should be formed from the reaction of CH*4 and O*2?

F. What is the maximum number of molecules of CO*2 that can be formed in this reaction?

G. If the reaction only produces 3.0 g of CO*2, calculate the percent yield of CO*2.

H. When CO*2 (g) and H*2O (g) are formed, the pressure within their container is 2 atm and the temperature is 25 degrees Celcius. What total volume (in L) do these gases occupy?

I. If the container from problem H is heated to 50 degrees Celcius, what final volume (in L) will these gases occupy?

#### Solution Preview

We have the equation, check whether it is balanced...

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<br>CH4 + O2 ---> CO2 + H2O

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<br>balance the equation first.. CH4 + 2O2 --> CO2 + 2H2O

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<br>b) CH4 --Methane, O2---Oxygen, CO2---Carbondioxide and H2O--water

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<br>c) From the balanced equation we can see that 2 moles of O2 reacts with one mole of CH4

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<br>d) How many grams of O2 react with the 1 mol of CH4?

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<br>Molecular mass of O2 = 32gm/mole (==> 1mole weighs 32 gm)

<br>From answer c, 1mole of CH4 requires 2 moles of O2, which implies 1 mole of CH4 requires 2*32 = 64gm of O2 ---Ans

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<br>E. How many grams of CO2 should be formed from the reaction of CH4 and O2?

<br>Molecular ...

#### Solution Summary

All questions answered with proper steps and explanations. A good collection of practice problems.