ChemIONS

I need assistance with some conversions, could someone please help. Thanks!

1.Convert 6 X 10^20 molecules of O2 to grams 2. Consider the following equation. From the quantity given, determine the number of moles of the other quantities of interest. C7 H12 + 11O2 ---> 7CO2 + 8H2O Given 0.1 mole O2 moles of H2O? 3. Calculate the number of moles of aspirin C9 H8 O4 in a 4.0 g tablet

Hi teresa, I think this will help: 1. to convert to grams of oxygen molecules, know that 6.02 * 10 ^ 23 molecules of oxygen, equivalent to a mole and a mole of oxygen weighs 32g. Use conversion factors. The answer is 0.031g 2. If 0.1 mol of O2 is the limiting reagent, then use a rule of 3: 11 moles of 02 produced 8 mol of water, 0.1 mol of o2 then produce 0.072 moles of water 3.A molecular weight of aspirin is: 180 g / mol then 4 grams is equivalent to 0.0222 moles of aspirin, for which mol = mass / molecular weight

Thank you so very much for your help! The way you explained it makes much more sense than my instructor's version. Have a great day!

Ok. If you need more help tell me and I help you . Have a great day too!

Hey Carlo, it's me again. My instructor told me to assume that the #2 question above is balanced. I come up with an answer of 1.59 and I wanted to double check because you know what you're doing and I'm not so sure about myself! lol! Anyway, if you could please rework it without first balancing it and round to the nearest hundredth, I'd appreciate it. It would have been much nicer if my instructor would have mentioned that before, huh?!! Thanks again!

hello Teresa! Well, do not worry, if your instructor told you it was not without the coefficients is, without the balance would be: It is also used a rule of three, but I think what happens is that the equation is unbalanced, that the coefficients are not correct, and I am sure that if the exercise is to do with the coefficients of the equation balanced. If no coefficients 1 mol O2 produces 1 mole of water and 0.1 mol of O2 also produce 0.1 mol of water. So I think we should re-balance the equation thus: (The numbers are not good) C7H12 + 10 O2 ---> 7 CO2 + 6 H2O these are the correct coefficients: so now if I use the rule of three: 10 moles of O2 produce 6 moles of water, 0.1 mol of O2 then produced: 0.06 moles. I do not think they produce more moles and I'm sure the answer is part of a small amount (0.1 moles of O2) Please review this solution and if the answer of 0.06 is not what you want, tell me and I'll help you find If you need help do not hesitate to find me and have a great day!

I'm sorry but I don't think it is 20 O2..... remember you have to conservate the mass of O2. Check out your answer again. Mr Vader... be careful