The reaction of a hydrocarbon with water is called hydrofusion. This is a term that has been used since the early twentieth century, when chemists first began to study the interplay between hydrocarbons and water.
Hydrofusion was discovered in 1907 by American chemist Walter N. Lewis, who also coined the term “catalyst” in relation to chemical reactions.
In his research, Lewis found that when acetone (another common chemical name for methylethylketone) was exposed to water, it produced acetone hydrate—a compound consisting of one acetone molecule linked to one water molecule—as well as some unreacted acetone.
This discovery led to the conclusion that when acetone comes into contact with water, it acts as a catalyst for the breakdown of H2O into HO+- (hydroxyl) ions.
Divide the moles of C3h8 by 8
Now let’s figure out how many molecules of water are formed when five moles of propane react. You divide the moles of C3h8 by 8, which would be 0.625 mol/L.
This is not a normal unit measurement, but it is a useful one. It means that 0.625 mole per liter of liquid produces one molecule of water.
So, five moles of propane dissolved in eight liters of liquid produces 0.625 mole/L of water, or .6 mole/liter. This is how much water is produced for every molecule of propane that reacts.
There are several ways to express the amount of water produced, but the most universal way is in molecules per million (ppm) molecules of compound present.
Multiply by 2
To calculate how many molecules of water are formed when five moles of ethane react, you must multiply the number of moles of ethane by two.
So, if five moles of ethane react, ten molecules of water are formed. To be more specific, ten molecules of HO are formed when five moles of ethane react.
This is due to the fact that a chemical reaction does not create or remove atoms, only combines them in different ways. When one molecule of ethane reacts with one molecule of HO, they combine to form one molecule of ethanewater solution.
There are no new atoms created, only old ones rearranged. This is important to remember when calculating how many molecules of a certain substance are produced in a reaction.
Calculate the number of moles of O2
Now that you know how many moles of carbon monoxide there are, you can calculate how many moles of oxygen are produced when one mole of carbon monoxide reacts with one mole of water.
One mole of O2 is produced for every two moles of H2O. Since you know the volume of the water molecule (1 L), you can calculate how many molecules of oxygen are produced. One liter contains 1 million molecules, so 1 L of water contains 1 million molecules of oxygen.
There were 5.0 moles of C3H8 originally, so if all five moles reacted, then 2 million molecules of oxygen would be produced. That is not the correct answer! There was not enough water present for that much oxygen to be produced.
Divide the moles of O2 by 2
Next, you must calculate how many moles of O2 are produced when five moles of C3H8 are burned. To do this, divide the number of moles of O2 by two.
So, 5mol O2 / 2 = 2mol O2
Two molecules of oxygen = 2 ÷ 8 = 0.
Multiply by 18
In this case, you would need to multiply your answer by 18 in order to get the correct answer. So, if five moles of C3h8 reacted, eighteen molecules of water would be formed.
This is because five moles of C3h8 reacts with six moles of O2, and each mole of O2 requires two molecules of water to form the product CO2. Since there is already a molecule of water per carbon atom in C3h8, adding an extra one per molecule required for the reaction with oxygen would be enough.
You may have noticed that 18 is the same number as two times twelve. This is because there are twelve atoms of carbon in a molecule of C3h8, so two times that is twenty-four atoms. Twelve plus twenty-four is thirty-six, which is also eighteen.
You did not need to know this fact in order to answer the question correctly, but it helps clarify why the answer was eighteen instead of some other number.
Add the final two numbers together
Once you have your final answer, you must add the two numbers (moles of carbon x mole ratio of carbon dioxide:mole ratio of water) together to get the total number of molecules.
This is very important! You could get the correct answer for how many moles of carbon dioxide are formed, but if you do not add in the water molecules, your answer will be incorrect.
For example, if five moles of C3H8 react, how many molecules of water are formed? First, solve for how many moles of water are formed: 5 mol/6 mol = 1 mol WAtotal. Then, add in the number of carbon atoms that react and form carbon dioxide: 5 + 6 = 11 carbons x 2 atoms/carbon = 22 carbon atoms that react.
Therefore, there are 11 molecules of water formed for every 22 molecules of carbon dioxide produced.
Round to two decimal places
Stoichiometry problems also often involve determining the number of molecules formed or consumed when a reaction occurs. When a chemical reaction produces a molecule, that molecule is said to be produced in excess.
When a chemical reaction consumes a molecule, that molecule is said to be consumed in deficiency. For example, if you have five cups of water and you want to produce two cups of chlorine, how much chlorine should you use?
You would need to use more chlorine than what is present in five cups of water, otherwise you would not achieve the desired amount. This question can be answered by solving the stoichiometry problem for chlorine (Cl2) and water (H2O).
Once you solve the problem for Cl2 in H2O, you will get the number of Cl2 molecules used and how many H2O molecules are consumed.
