Question

Mathematically combine the three given reactions so that they sum to give a balanced chemical equation describing the production of propane C3H8(g), from its elements, C(s.graphite) and H2lg). Show your intermediate steps. For example, if you must reverse reaction (c), enter the reverse in the appropriate answer box; if you multiply reaction (a) by 2, enter the updated equation in the corresponding answer box. Make sure to enter the overall balanced equation at the bottom (a) C3Hg(g)+502C2+H2O0) (b) C(s)+02(g)> CO2(g) (c) H2(«)+ 7o(Hod)

Answer 1

Answer and Explanation

The final reaction is the production of propane from Carbon and Hydrogen.

3C (s) + 4H2 (g) ---> C3H8 (g)

So, reverse eq. A,

3CO2 (g) + 4H20 (l) ---> C3H8 (g) + 502 (g)

Add 3 × eq. B,

3C (s) + 3O2 (g) ----> 3CO2 (g)

Add 4 × eq. C,

4H2 (g) + 2O2 (g) ---> 4H20 (l)

Writing them together,

3CO2 (g) + 4H20 (l) ---> C3H8 (g) + 502 (g)

+ 3C (s) + 3O2 (g) ----> 3CO2 (g)

+ 4H2 (g) + 2O2 (g) ---> 4H20 (l)

------------------------------------------------------------

3CO2 (g) + 4H20 (l) + 3C (s) + 3O2 (g) + 4H2 (g) + 2O2 (g) ---> C3H8 (g) + 502 (g) + 3CO2 (g) + 4H20 (l)

The compounds that exist on both sides cancel out and we're left with

3C (s) + 4H2 (g) ---> C3H8 (g)

So, mathematically, the final reaction can be written as:

(-eq. A + 3(eq. B) + 4(eq. C))

-A+3B+4C = 3C (s) + 4H2 (g) ---> C3H8 (g)

QED!