ChemistryGeneralQuality 86 · Exceptional

Balancing Chemical Equations Step by Step

PR
Xena TobinTeacher Tier
@author · 2026-08-13 · v1
7 min read
Balancing conserves atoms on both sides. For
C3H8+O2→CO2+H2OC_3H_8 + O_2 \to CO_2 + H_2O
, start with carbon: 3 on the left means 3
CO2CO_2
. Then hydrogen: 8 means 4
H2OH_2O
. Then count oxygen:
3×2+4×1=103\times2 + 4\times1 = 10
on the right, so 5
O2O_2
. Final:
C3H8+5O2→3CO2+4H2OC_3H_8 + 5O_2 \to 3CO_2 + 4H_2O
.
0 teacher endorsements

Discussion

Comments support LaTeX — write ∫01x2 dx\int_0^1 x^2\,dx inline with $...$.

Sign in to join the discussion.

Aisha Khan
24 days ago
The line "Balancing conserves atoms on both sides" is the part that finally made it click for me. I'd been fuzzy on balancing before — seeing it spelled out this way connects it to equations in a way my notes never did. The c3h8+o2→co2+h2oc_3h_8 + o_2 \to co_2 + h_2o bit is a nice touch too.
Ethan Park
24 days ago
Yeah, the balancing point is exactly right. I'd add that equations matters here too — if you drop it, the conserves case breaks down even though it *looks* optional. Learned that the hard way on a problem set last week.
Noah Williams
24 days ago
Quick question on balancing: does that also explain what happens with equations? My textbook mentions both but never ties them together, and this explanation of conserves makes me think they're the same mechanism from two angles.
Olivia Murphy
24 days ago
Adding to this: "Balancing conserves atoms on both sides" also generalizes to equations. I tried it on conserves and the same logic holds, which makes me think balancing is the deeper principle behind all of them. The c3h8+o2→co2+h2oc_3h_8 + o_2 \to co_2 + h_2o detail is what trips people up though.
Maria Santos
24 days ago
What stood out is "For C3H8+O2→CO2+H2OC_3H_8 + O_2 \to CO_2 + H_2O, start with carbon: 3 on the left means 3 CO2CO_2" — most resources skip the *why* and just give the formula. Adding equations to the picture is what makes balancing feel like a real tool instead of trivia. Saved this one.