The arrow in the middle of a chemical equation means this....?
1 Answer
Yields...
It just tells you that the reaction in that direction yields the product on the other end.
#"C"(gr) + 1/2"O"_2(g) -> "CO"(g)#
This is a formation reaction, and it says that mixing 1 mol of carbon graphite and half a mol of dioxygen gas reactant under the appropriate conditions would theoretically yield 1 mol of carbon monoxide gas product.
If for some reason I wrote:
#"C"(gr) + 1/2"O"_2(g) larr "CO"(g)#
I would really be saying:
#"CO"(g) -> "C"(gr) + 1/2"O"_2(g)#
which is the reverse reaction to the first one at the top of the page. In this case, carbon monoxide gas is the reactant instead of the product.
If for some reason, both reaction directions are similarly favored in terms of thermodynamics, then it is appropriate to write this as an equilibrium:
#"C"(gr) + 1/2"O"_2(g) rightleftharpoons "CO"(g)#
And in this case,
