MYTUTOR SUBJECT ANSWERS

986 views

What mass of carbon dioxide is produced from burning 100 grams of ethanol in oxygen according to this reaction: C2H5OH + 3 O2 --> 2 CO2 + 3 H2O

When approaching a question like this I always find it easier to write out the equation with the known quantities written underneath each individual compound.  This allows us to easily check whether the equation is balanced

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

We can see that this equation is balanced as it has 2 carbons, 6 hydrogens, and 7 oxygens on each side.

We are trying to work out the mass of CO2 and we already know what mass of ethanol (C2H5OH) we have.  We can also work out the gram formula mass of each compound we are interested in. 

gfm CO2 = (1 x 12) + (2 x 16) = 44 g/mol

gfm C2H5OH = (2 x 12) + (6 x 1) + (1 x 16) = 46 g/mol

Next we need to decide what formula we can use to figure out the mass of CO2 from the data that we have. 

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

                       m = 100 g                                            m = ?

                       gfm = 46 g/mol                                gfm = 44 g/mol

Using n = m/gfm we can figure the number of moles of ethanol.  We can use this to work out the number of moles of carbon dioxideas these can be directly compared. 

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

                      n = m/gfm                      

                      = 100/46                         

                      =2.174 moles                 

The mole ratio of ethanol to carbon dioxide is 1:2. So by multiplying our number by 2 we get the number of moles of CO2.

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

                n = moles of C2H5OH x 2

           = 2.174 x 2

           = 4.349 moles

Now that we have the number of moles of carbon dioxide we can figure out the mass produced by using the formula m = n x gfm

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

                                                                                    m = n x gfm                       

                                                                                        = 4.349 x 44                 

                                                                                        = 191.3 g

Therefore, the mass of carbon dioxide is produced from burning 100 grams of ethanol in oxygen is 191.3g.

Katherine M. GCSE Chemistry tutor, A Level Chemistry tutor, GCSE Biol...

1 year ago

Answered by Katherine, a GCSE Chemistry tutor with MyTutor


Still stuck? Get one-to-one help from a personally interviewed subject specialist

218 SUBJECT SPECIALISTS

£18 /hr

Jamie H.

Degree: Clinical Dentistry (Bachelors) - Sheffield University

Subjects offered:Chemistry, Science+ 2 more

Chemistry
Science
French
Biology

“I am a third year dental student at The University of Sheffield. I am really passionate about my subjects and am keen to pass this on to others!”

£24 /hr

Beth W.

Degree: English Literature (Bachelors) - Cambridge University

Subjects offered:Chemistry, History+ 6 more

Chemistry
History
English Literature
English Language
Biology
.ELAT
-Personal Statements-
-Oxbridge Preparation-

“I am currently a student at the University of Cambridge reading English literature. Throughout GCSE and A-Level English literature I accrued full marks in every formal, externally marked assessment. I have a limitless passion for my s...”

£22 /hr

Runzhi C.

Degree: Medicine (Bachelors) - Imperial College London University

Subjects offered:Chemistry, Maths+ 3 more

Chemistry
Maths
Biology
-Personal Statements-
-Medical School Preparation-

“Hi there, I am a first year medical student at Imperial College London and I have lived in the UK all my life. I enjoy studying medicine because it encompasses both scientific knowledge and social aspects. I am relatively new to tutor...”

About the author

Katherine M.

Currently unavailable: for regular students

Degree: Chemistry (Masters) - Edinburgh University

Subjects offered:Chemistry, Maths+ 1 more

Chemistry
Maths
Biology

“All About Me Hi, my name is Katherine I am from Edinburgh and am currently in my 2nd year studying Medicinal and Biological Chemistry, also in my home town, at the University of Edinburgh.  I have always had a real passion for science...”

You may also like...

Posts by Katherine

What mass of carbon dioxide is produced from burning 100 grams of ethanol in oxygen according to this reaction: C2H5OH + 3 O2 --> 2 CO2 + 3 H2O

Q: How to solve the simultaneous equations 3x+2y=7 and 5x+y=14

Other GCSE Chemistry questions

Why can graphite conduct electricity?

What is the equation for complete combustion and what does it require?

How do I calculate the relative formula mass of Calcium carbonate (CaCO3)

What is it about the structure and bonding of graphite that allows it to conduct electricity?

View GCSE Chemistry tutors

We use cookies to improve your site experience. By continuing to use this website, we'll assume that you're OK with this. Dismiss

mtw:mercury1:status:ok