Answer the following question: Ethanol, C2H5OH, is considered clean fuel because it burns in oxygen to produce carbon dioxide and water with few trace pollutants. If 500.0 g of H2O are produced during the combustion of ethanol, how many grams of ethanol were present at the beginning of the reaction? When answering this question include the following: -Have both the unbalanced and balanced chemical equations.
-Explain how to find the molar mass of the compounds.
-Explain how the balanced chemical equation is used to find the ratio of moles (hint: step 3 in the video).
-Explain how many significant figures your answer needs to have.
The numerical answer
Your

127.88 grams of ethanol were present at the beginning of the reaction

Explanation:

Firstly, let's make the combustion reaction:

C₂H₅OH  +  3O₂  →  2CO₂  +  3H₂O

By 1 mol of ethanol, you can make 3 moles of water.

A Mole of water = Water mass / Molar mass

150g / 18g/m = 8.3 mole

3 mole of water came from 1 mol of ethanol

8.3 mole came from (8.3 .1)/3 = 2.78 mole of ethanol

Molar mass ethanol = 46 g/m

Mole . molar mass = mass

2.78 m .  46g/m = 127.88 g

you need to take a look at the periodic system in order to sort these elements into pairs that would most likely exhibit similar chemical properties. first, you need to find elements that are found in the same group (groups are vertical in the periodic system), and then to see whether they have the same valence number. if they meet these criteria, they will have similar properties.

the first pair: ne (neon) and kr (krypton), are noble gases found in group 8

the second pair: li (lithium) and k (potassium), found in group 1

the third pair: s (sulfur) and te (tellurium), found in group 6

sure im new too!

explanation: