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Ethanol, C2H5OH burns with oxygen in air to give carbon dioxide and water. what is the...

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chocolate975 | Student, Undergraduate | (Level 2) Honors

Posted September 6, 2010 at 3:41 AM via web

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Ethanol, C2H5OH burns with oxygen in air to give carbon dioxide and water. what is the amount  (in moles) of water produced from 0.51 mol C2H5OH.

the equation is C2H5OH + 3O2 -----> 2CO2 + 3H2O

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ndnordic | High School Teacher | (Level 2) Associate Educator

Posted September 6, 2010 at 5:02 AM (Answer #1)

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This is an example of a combustion reaction.  To answer this you must first balance the equation.

The easiest way is to set up the reaction equation without any coefficients:

C2H6O + O2 -->  CO2  + HOH

Now start balancing, first with carbon, then with hydrogen and last the oxygen.

There are 2 carbons on the left  and 6 hydrogens so you add a coefficient of 2 in front of the CO2 and a 3 in front of the water.

C2H6O  +  O2 -->  2 CO2  +  3 HOH

Now count the number of oxygen on the product side and you get seven.  One oxygen came from the ethanol so you need 6 more from oxygen. Add a coefficient of 3 in front of the oxygen on the reactant side and your reaction is balanced.

C2H60  + 3 O2  -->  2 CO2  +  3 HOH

This shows you that for every mole of ethanol, you will get 3 moles of water.  So if you start with 0.51 moles of ethanol, you will produce 3 x .51 or 1.53 moles of water.

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neela | High School Teacher | (Level 3) Valedictorian

Posted September 6, 2010 at 11:17 PM (Answer #2)

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The combustion equation is  C2H5OH +3O2 = 2CO2 + 3H2O.

The given equation is a balanced equation.

To find the  amount of mole  of water produced when 0.51 mole of Ethanol , C2H5OH is burnt and cobines with oxygen.

The equation self explains that :

One mole of (C2H5OH) +3mole of (O2) results in products of 2 mole of (CO2) and 3moles of(H2O).....(1)

Threfore if you multiply the equation at (1) by 0.51 we get:

0.51 mole of  (C2H%OH) + 3*(0.51)mole of (O2(O2) results in products of 2*(0.51) mole of (CO2) and 3*(0.51) mole of (H2O).

So  the equation  answers that 3*0.51 mole of H2O is produced.

3*0.51 mole of  H2O  = 1.53 mole of water is produced when 0.51 mole of Ethanol is combined(burned in) with oxygen.

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rwsss | eNotes Newbie

Posted June 2, 2013 at 10:45 AM (Answer #3)

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You could have just used a universal chemistry problem solver at www.xreact.org

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Yojana_Thapa | Student, Grade 10 | (Level 1) Valedictorian

Posted January 27, 2014 at 1:04 AM (Answer #4)

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C2H5OH + 3O2 -----> 2CO2 + 3H2O

amount  (in moles) of water produced from 0.51 mol C2H5OH?

XmoLH2O / 3moL = 0.51moLC2H5OH / 1moL

- now we cross multiply

1.53 moL of water is produced from 0.51 mol C2H5OH.

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parama9000 | Student, Grade 11 | (Level 1) Valedictorian

Posted January 27, 2014 at 1:03 PM (Answer #5)

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1.53 moL of H20

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Jyotsana | Student, Grade 10 | (Level 1) Valedictorian

Posted February 1, 2014 at 12:27 AM (Answer #6)

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0.51mole C2H5OH/ 1mol=mole H20/ 3mol

1.53/1= 1.53

x= 1.53 mole of H2O

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nicole8923 | Student, Grade 10 | (Level 1) Salutatorian

Posted February 26, 2014 at 8:03 PM (Answer #7)

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0.51*3=1.53

1.53/1

x=1.53mole of H2O

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