Question

Consider the combustion reaction of acetylene (C2H2) : 2C2H2 + 5O2 mc001-1.jpg 4CO2 + 2H2O Use the periodic table to determine how many grams of oxygen would be required to react completely with 859.0 g C2H2?

Answer 1

1) Balanced chemical equation:

    2C2H2 + 5O2 ----> 4CO2 + 2H2O


2) State the molar ratios


     2 mole C2H2 : 5 mole O2 : 4 mol CO2 : 2 mole H2O


3) Use the periodic table to get the atomic masses of each element and from that the molar masses of O2 and C2H2


Atomic masses:

O: 16 g / mol

C: 12 g / mol

H: 1 g / mol


Molar masses of O2 and C2H2:


O2: 2 * 16 g/mol = 32 g/mol

C2H2: 2*12 g/mol + 2*1g/mol = 26 g / mol


3) Convert 859.0 grams of C2H2 into moles:


     859.9 g / 26.0 g /mol = 33.07 mol C2H2


4) State the molar proportion with C2H2 and O2


x mol O2 / 33.07 mol C2H2 = 5 mol O2 / 2 mol C2H2


=> x = 33.07 mol C2H2 * 5 mol O2 / 2 mol C2H2 =   82.68 mol O2


5) Convert 82.68 mol O2 to grams


82.68 mol * 16 g/mol = 1322.9 g O2.



Answer: 1322.9 grams of O2

Answer 2

Answer:

2643.08g of O2

Explanation:

Step 1:

The balanced equation for the reaction. This is given below:

2C2H2 + 5O2 —> 4CO2 + 2H2O

Step 2:

Determination of the masses of C2H2 and O2 that reacted from the balanced equation. This is illustrated below:

2C2H2 + 5O2 —> 4CO2 + 2H2O

Molar Mass of C2H2 = (12x2) + (2x1) = 24 + 2 = 26g/mol

Mass of C2H2 from the balanced equation = 2 x 26 = 52g

Molar Mass of O2 = 16x2 = 32g/mol

Mass of O2 from the balanced equation = 5 x 32 = 160g

From the balanced equation above,

52g of C2H2 reacted with 160g of O2.

Step 3:

Determination of the mass of oxygen that would be required to react completely with 859.0g of C2H2.

This is illustrated below:

From the balanced equation above,

52g of C2H2 reacted with 160g of O2.

Therefore, 859g of C2H2 will react with = (859 x 160)/52 = 2643.08g of O2.

From the calculations made above, 2643.08g of O2 will react completely with 895g of C2H2.