Answer: Molarity of 
in the original sample was 1.96M
Explanation:
Molarity is defined as the number of moles of solute dissolved per liter of the solution.
Now put all the given values in the formula of molarity, we get
Thus molarity of in the original sample was 1.96M
The balanced chemical equation of the reaction described above is,
C2H6O + O2 --> H2O + C2H4O2
If we have 3.84 g of oxygen, we divide by its molar mass.
n = (3.54 g Oxygen gas) x (1 mole O2/ 32 g O2)
n = 0.11 moles O2
Using ratio and proportion,
number of moles of ethanol = (0.11 moles O2) x (1 mole C2H6)
= 0.11 moles C2H6
Then, we multiply the calculated value to its molar mass, 46 grams /mol.
mass of ethanol = (0.11 mol) x (46 grams / mol)
= <em>5.06 grams</em>
Heat needed=mcθ
=7×0.031×(42-17)
=5.425cal
Hydrogen and carbon atoms
Explanation:
Hydrocarbons are molecules that are made up of hydrogen and carbon atoms only.
They are made up of covalent bonds between the carbon and hydrogen atoms.
There is a wide range of hydrocarbons due to the unique properties of carbon.
Most of the hydrocarbons comes from crude oil, natural gas and coal.
When hydrocarbons burn, they produce water and carbon dioxide alone.
They are used as fuel in industrial processes because they produce heat energy.
learn more:
Hydrocarbons brainly.com/question/6126420
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