Garlic Bread #1

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marg44
Posts: 18
Joined: Fri Sep 28, 2018 12:24 am
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Garlic Bread #1

Postby marg44 » Sun Nov 04, 2018 11:09 pm

Can someone help me with #1? I tried a couple things but I keep getting wild numbers.

Cody Do 2F
Posts: 62
Joined: Fri Sep 28, 2018 12:23 am

Re: Garlic Bread #1

Postby Cody Do 2F » Mon Nov 05, 2018 11:12 am

First, set up a chemical equation to help see where everything lies:
CxHxOx + O2 --> CO2 + H2O.

Then, you divide the molar mass of CO2 (44.011g) by that of Carbon (12.01g). This will give you about .2729. This value represents that 27.29% of the CO2 produced is carbon. Multiply .2729 by the amount of CO2 (.561g) to get .153 grams of Carbon. This carbon must have come from the isopropyl alcohol, seen through the chemical equation.

Now divide the molar mass of H2O (18.02g) by that of Hydrogen (2.02g). This will give you .112, which you will multiply with the amount of hydrogen (.306g) to get .034 grams of Hydrogen. This hydrogen must have come from the isopropyl alcohol, seen through the chemical equation.

Now take the amount of isopropyl alcohol (.255g) and subtract the amount of Carbon and Hydrogen to get .086 grams. This is the amount of oxygen in the isopropyl alcohol. Now that you have the grams of each element, use the molar mass of carbon, hydrogen, and oxygen to find the moles of each element (.0128 moles C, .0343 moles H, and .00425 moles O). Divide all the values by the smallest value of moles (.00425 moles O). This will give you C3H6O1!

Nina Do 4L
Posts: 61
Joined: Fri Sep 28, 2018 12:27 am

Re: Garlic Bread #1

Postby Nina Do 4L » Mon Nov 05, 2018 10:04 pm

First, convert all that was given in the equation to moles.

.561 g CO2*(1mol Co2/44.01 g CO2)
Then, use the mole ratio of how many carbons there are in CO2. So your entire table should look something like:
.561 g CO2*(1mol Co2/44.01 g CO2)*(1 mol C/1 mol CO2) CO2 is on the Botton to cancel out, leaving you with .0127 moles of C, or (.153 g Carbon if you multiply .01267*12.01).

Do the same for hydrogen but do not forget that one mole of H2O gives you 2 hydrogens!
.306 mol H2O*(1 mol H2O/18.02 g H2O)*(2 mol H/ 1 mol H2O)= .0339 g Hydrogen or .0342 g Hydrogen.

Add the grams of Carbon and Hydrogen then subtract by .255 g of the compound to find the amount of grams of oxygen (.255 given in question).

.0678 g O*(1 mol O/16g O)= .0042375 mol O or .0678 grams Oxygen.

Then, divide by the smallest amount of moles, which is oxygen in this case.


That'll then give you 3 carbons, 8 hydrogens, and an oxygen. Hope this helped!


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