Problem 101
In the manufacturing of computer chips, cylinders of silicon are cut into thin wafers that are \(3.00\) inches in diameter and have a mass of \(1.50 \mathrm{~g}\) of silicon. How thick \((\mathrm{mm})\) is each wafer if silicon has a density of \(2.33 \mathrm{~g} / \mathrm{cm}^{3} ?\) (The volume of a cylinder is \(\left.V=\pi r^{2} h .\right)\)
Problem 102
A sunscreen preparation contains \(2.50 \%\) by mass benzyl salicylate. If a tube contains \(4.0\) ounces of sunscreen, how many kilograms of benzyl salicylate are needed to manufacture 325 tubes of sunscreen?
Problem 104
The label on a 1-pint bottle of mineral water lists the following components. If the density is the same as pure water and you drink 3 bottles of water in one day, how many milligrams of each component will you obtain? a. calcium \(28 \mathrm{ppm}\) b. fluoride \(0.08\) ppm c. magnesium \(12 \mathrm{ppm}\) d. potassium \(3.2 \mathrm{ppm}\) e. sodium \(15 \mathrm{ppm}\)
Problem 105
a. Some athletes have as little as \(3.0 \%\) body fat. If such a person has a body mass of \(65 \mathrm{~kg}\), how many pounds of body fat does that person have? b. In liposuction, a doctor removes fat deposits from a person's body. If body fat has a density of \(0.94 \mathrm{~g} / \mathrm{mL}\) and \(3.0 \mathrm{~L}\) of fat is removed, how many pounds of fat were removed from the patient?
Problem 106
An 18 -karat gold necklace is \(75 \%\) gold by mass, \(16 \%\) silver, and \(9.0 \%\) copper. a. What is the mass, in grams, of the necklace if it contains \(0.24\) oz of silver? b. How many grams of copper are in the necklace? c. If 18 -karat gold has a density of \(15.5 \mathrm{~g} / \mathrm{cm}^{3}\), what is the volume in cubic centimeters?
Problem 107
A graduated cylinder contains three liquids \(\mathrm{A}, \mathrm{B}\), and \(\mathrm{C}\), which have different densities and do not mix: mercury \((\mathrm{D}=13.6 \mathrm{~g} / \mathrm{mL})\), vegetable oil \((\mathrm{D}=0.92 \mathrm{~g} / \mathrm{mL})\), and water \((\mathrm{D}=1.00 \mathrm{~g} / \mathrm{mL}) .\) Identify the liquids \(\mathrm{A}, \mathrm{B}\), and \(\mathrm{C}\) in the cylinder.
Problem 108
A mouthwash is \(21.6 \%\) ethyl alcohol by mass. If each bottle contains \(0.358\) pt of mouthwash with a density of \(0.876 \mathrm{~g} / \mathrm{mL}\), how many kilograms of ethyl alcohol are in 180 bottles of the mouthwash?
