Not understanding how to determine Stoichiometric air to fuel ratio

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To determine the stoichiometric air to fuel ratio for the given fuel oil containing 86% carbon and 14% hydrogen, start by considering a 100g sample of the fuel. Calculate the moles of carbon and hydrogen based on their mass percentages, assuming complete combustion where carbon converts to carbon dioxide and hydrogen to water. Use the molar amounts to find the total oxygen required for combustion, factoring in air composition, which is 23% oxygen and 77% nitrogen. From this, derive the stoichiometric air to fuel ratio by calculating the total air needed for the combustion process. This approach will provide a clear understanding of how to solve similar stoichiometric problems.
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Homework Statement


Hey, just doing a few problems and i have found i have no understanding of how to solve these types of question, if anyone can help or provide info it would be great thanks...

Q " The fuel oil supplied to a boiler contains 86% carbon and 14% hydrogen by mass. Determine the stoichiometric air to fuel ratio for complete combustion of the fuel."


Homework Equations



Composition of air by mass : Oxygen 23% Nitrogen 77%

Relative Atomic Mass Oxygen (O) 16 , Carbon (C) 12 Hydrogen (H) 1

The Attempt at a Solution

 
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Consider a basis of 100g of the fuel. Based on the mass percentage composition of the fuel, you should be able to work out how many moles of carbon and hydrogen in this 100g basis.

You should be able to assume that all of the carbon becomes carbon dioxide and all of the hydrogen becomes water. Based on the molar amounts of carbon and hydrogen, you can work out how much water and carbon dioxide will form and thus the amount of oxygen consumed.

Can you work from there?
 
So basically create an equation and then sub in the molar amounts??
 
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