Category: Chemical Engineering Math
"Published in Newark, California, USA"
Calculate the molarity of a solution containing 10.0 grams of sulfuric acid in 500 mL of solution. (MW of H2SO4 is 98.1)
Solution:
The molarity of a solution is defined as the number of moles of a solute per liter of a solution.
In this problem, the weight of solute which is sulfuric acid and the volume of the solution are given.
The number of moles of sulfuric acid is
Therefore, the molarity of sulfuric acid solution is
Category: Chemical Engineering Math
"Published in Vacaville, California, USA"
Acetone is the chemical solvent present in the fingernail polish remover. Its percent composition is 62.0% carbon, 10.4% hydrogen, and 27.5% oxygen. What is the empirical formula for the compound?
Solution:
Basis: 100 grams of sample
Weight of each components:
Weight of carbon is
Weight of hydrogen is
Weight of oxygen is
Moles of each components:
Moles of carbon is
Moles of hydrogen is
Moles of oxygen is
From
the number of moles of each component, we need to divide all of them by
their least number of moles which is oxygen in order to get the number
of atoms in a sample.
Number of carbon in a sample is
Number of hydrogen in a sample is
Number of oxygen in a sample is
Therefore, the empirical formula for acetone is
Category: Chemical Engineering Math
"Published in Vacaville, California, USA"
Percent composition data for the chlorofluorocarbon Freon-12 by mass are: 9.933% carbon, 58.63% chlorine, and 31.44% fluorine. Based on these data, what is the empirical formula of Freon-12?
Solution:
Basis: 100 grams of sample
Weight of each components:
Weight of carbon is
Weight of chlorine is
Weight of fluorine is
Moles of each components:
Moles of carbon is
Moles of chlorine is
Moles of fluorine is
From the number of moles of each component, we need to divide all of them by their least number of moles which is carbon in order to get the number of atoms in a sample.
Number of carbon in a sample is
Number of chlorine in a sample is
Number of fluorine in a sample is
Therefore, the empirical formula for Freon-12 is
