Transcript for:
Understanding Mole to Mole Ratios

Now what is a mole to mole ratio? A mole to mole ratio is a conversion factor that allows you to go from one compound to a completely different compound. You know to use a mole to mole ratio when you are trying to change your compounds. Now where do you find the numbers for that multiple ratio? In your balanced equation. When you're balancing equations you have a coefficient in front of a compound or a number in front of a compound. That is what you use in a mole to mole ratio. Let's try some. How many moles of H2O are produced when 2.5 moles of O2 reacts with H2. We're given 2.5 moles of O2 and you're finding moles of H2O. Notice we're going from O2 to H2O so we're changing our compound. We have to use a mole to mole ratio. Where we get that multiple ratio is from our balanced equation. Your setup will be with our given, first. That 2.5 moles of O2 on top aligning your moles of O2 across from each other so they can cancel and put what you're finding the moles of H2O on top. Where we're going to take these numbers for our mole to mole ratio is from the balanced equation. If there is no original number assume it's just a 1. There's one mole and two moles of H2O multiply straight across and you get 5.0 moles of H2O. Now I really want us to understand this concept so let's do another example so we could really master this. How many moles of O2 are in 7.03 moles of CO2? We're given the 7.03 moles of CO2 and going to moles of O2. We're changing the compound again so we have to use our mole to mole ratio from our balanced equation. You're setup with your given on top, the 7.03 moles of CO2. Aligning those moles of CO2 across from each other so they can cancel and placing the moles of O2 on top. Once again we'll get our mole to mole ratio from our balanced equation. There are 5 moles of O2 per every 3 moles of CO2. Multiply straight across and divide by 3 and you get 11.7 moles of O2. Let's go ahead and put this into practice. I hope my videos are helping, I really just want you guys to succeed in Chemistry and everything that you decide to do in life. For more help check the description box below there are practice problems with step by step answers and reserve your spot today for live tutoring with myself where we're going to go into even more detail of understanding these concepts. Make sure to LIKE subscribe and I'll see you next time.