Balance the combustion reaction between propane and oxygen. If a coefficient of "1" is required, choose "blank" for that box.

C3H8 + O2 → CO2 + H2O

Question

Balance the combustion reaction between propane and oxygen. If a coefficient of "1" is required, choose "blank" for that box.

C3H8 + O2 → CO2 + H2O

jfraser · Answer

start with the carbons

anonymous · Answer

There's 3 in the first.
In the Third there's 1.

jfraser · Answer

so then how many CO2 molecules have to be made if each propane has 3?

anonymous · Answer

which is propane..?
this all is confusing.

jfraser · Answer

the C3H8 is the propane

anonymous · Answer

okay, so it's 1 CO2.

jfraser · Answer

no. it's 3 CO2

$$C_3H_8 + O_2 \rightarrow 3 CO_2 + H_2O$$

anonymous · Answer

okay. this is really frustrating sorry.

anonymous · Answer

i put in the first one 3.
second one i put 4.
third i put 4.
fourth i put 3.

jfraser · Answer

each propane molecule has 3 carbon atoms in it, but each carbon dioxide only has 1. In order to be balance, a reaction must have the same number of each kind of atom on each side. When 1 propane is reacted, 3 CO2's must be formed

jfraser · Answer

no.

anonymous · Answer

mkay.

jfraser · Answer

$$3C_3H_8 + 4O_2 \rightarrow 4CO_2 + 3H_2O$$
add up all the C atoms on the left hand side.

add up all the C atoms on the right hand side. Are they equal?

anonymous · Answer

yeah. 6 and 6

jfraser · Answer

no

anonymous · Answer

ok nevermind. its blank. 5. 3 and 4. corrrect now?

jfraser · Answer

how'd you do it?

anonymous · Answer

both sides have to be equal. so i made them equal.

jfraser · Answer

good, so try this one.$$C_5H_{12} + O_2 \rightarrow CO_2 + H_2O$$