Propane, commonly known as liquid petroleum (LP) gas, burns in air to yield CO₂ and H₂O. Write a balanced equation for the reaction.

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Hi, everyone. Welcome back. Let's look at the next problem. It says air reacts with butane, a highly flammable alkane to produce carbon dioxide and water. What is the balanced equation for the given reaction? And I have four different possibilities labeled A through D for this balanced reaction. Let's recall, this is a combustion reaction. So let's write out the general form and then we'll work on getting the proper coefficients. So we have butane butane is a four carbon alkane. So we'll write out that formula as CH three ch two, ch two, ch three, it's gonna be on a gaseous form. So put G in parentheses plus, then I'm going to leave a space to fill in the coefficient as I figure that out. So it's going to react with air, more specifically the oxygen and air. So that would be in the form of 02 gas will become carbon dioxide and water as it combusts. So leave a space for the coefficient at CO2 which is a guess. And water H2O and it's in the form of water vapor since the combustion reaction. So our first step here will be to balance the carbon. So I'm going to draw a line to keep this straight. No, if I'm on a test and I speed is important, I first will take a quick look at my answer possibilities because I may be able to eliminate some right away. Since I have the basic format of my answer. More specifically, I see that I have two answer choices C and D that do not have the correct alkane here. So in choice C, my balanced equation includes a molecule that has 12345 carbons. So this is pentane, not butane. And that is the case also 12345 with choice D also involves pentane rather than butane. So we can eliminate choices C and D. So we only have choices A and B left. So let's start balancing our equation and see what coefficients we come up with because choices A and B only differ by the coefficients. So when we go to balance Carmen, we see that we have four carbons on the left side from butane and we have one carbon on the right side from carbon dioxide. So we are going to put the coefficient four in front of our co two. After balancing the carbon, we move on to balance the hydrogen on the left side from butane, we have three plus two plus two plus three. So that means we have 10 carbons or excuse me, I said carbon 10 hydrogens on the left side and then on the right side, our hydrogen is in the form of water and we have two hydrogens from the water. So that means we need to add a coefficient of five in front of water. Since it will be five times two, equal to 10, then our final step is to balance the oxygen. So on the left side, we have oxygen from 02. So that would be two on the left, on the right said there's oxygen in both the carbon dioxide and the water. So we have two oxygens in co2 times multiplied by four, which is the coefficient. So eight from our four carbon dioxides and then one oxygen in water multiplied by five is the coefficient five oxygen molecules or five oxygen atoms coming from the water. So on the left side, two, on the right side, 13, well, the way we'll deal with this at first is we're going to put a coefficient of 13 halves in front of oxygen that will put 13 on both sides. Then last of all, we deal with our fractional coefficient by multiplying the entire equation by two to get rid of that fractional coefficient. So when we do that, we'll end up with two buttons. I'm going to write these on top two butane multiplied by 1302 molecules and then that will lead to eight carbon dioxide molecules and 10 water molecules. So there's our coefficients. Now let's look at our answer choices to see which matches up well, right away, we can see that choice A has two butane molecules while choice B has just one. So choice B we can eliminate right away. It doesn't have the right coefficient in front of butane. So let's just double check our reaction. And choice A, we have two butane plus 1302 becomes eight co two plus 10 H2O. So choice A here is our balanced equation for this combustion reaction of butane. See you in the next video.

Propane, commonly known as liquid petroleum (LP) gas, burns in air to yield CO₂ and H₂O. Write a balanced equation for the reaction.

Verified video answer for a similar problem:

Key Concepts

Combustion Reaction

Balancing Chemical Equations

Stoichiometry

Propane, commonly known as liquid petroleum (LP) gas, burns in air to yield CO2 and H2O. Write a balanced equation for the reaction.

Verified video answer for a similar problem:

Key Concepts

Combustion Reaction

Balancing Chemical Equations

Stoichiometry

Propane, commonly known as liquid petroleum (LP) gas, burns in air to yield CO₂ and H₂O. Write a balanced equation for the reaction.