Solve for moles grams

label Chemistry
account_circle Unassigned
schedule 1 Day
account_balance_wallet $5

The complete combustion of octane, C8H18, the main component of gasoline, proceeds as shown below.

2 C8H18(l) + 25 O2(g) → 16 CO2(g) + 18 H2O(l)

(a) How many moles of O2 are needed to burn 1.00 mol of C8H18? 

(b) How many grams of O2 are needed to burn 1.75 g of C8H18? 

(c) Octane has a density of 0.692 g/mL at 20°C. How many grams of O2 are required to burn 3.35 gal of C8H18?

Jul 24th, 2015

Thank you for the opportunity to help you with your question!

a) ratio=2:25

25/2 =12.5moles

b) 12x8 + 18=114

32x1.75/114

=0.49122g

c) m=density x volume

=0.692x3.35

=2.3182g

Please let me know if you need any clarification. I'm always happy to answer your questions.
Jul 24th, 2015

Could you explain ur answer I dont get how you arrived

Jul 24th, 2015

first of all you get the ratio of octane to oxygen in the reaction, which is 2:25

using the same ratio, we get the no. of moles of O2 by (1molex25)/2=12.5moles

b) here, we use molar masses, O2=32g/mol , C8H18=12x8+1x18=114g/mol

since carbon=12 and hydrogen=1

Jul 24th, 2015

...You need to use more precise numbers like 12.01 and 1.01 please

Jul 24th, 2015

those ones are very precise, 12 and 1 are the rounded off ones, though still leads to almost the same answer value, but instead of 12 and 1 you may insert 12.01 and 1.01 respectively

Jul 24th, 2015

Studypool's Notebank makes it easy to buy and sell old notes, study guides, reviews, etc.
Click to visit
The Notebank
...
Jul 24th, 2015
...
Jul 24th, 2015
Sep 20th, 2017
check_circle
Mark as Final Answer
check_circle
Unmark as Final Answer
check_circle
Final Answer

Secure Information

Content will be erased after question is completed.

check_circle
Final Answer