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Problem 120
The mass of an average blueberry is 0.75 g and the mass of an automobile is 2.0×103 kg. Find the number of automobiles whose total mass is the same as 1.0 mol of blueberries.
- Suppose that atomic masses were based on the assignment of a mass of 12.000 g to 1 mol of carbon, rather than 1 mol of 12C. What would the atomic mass of oxygen be? (The atomic masses of carbon and oxygen, based on the assignment of 12.000 g to 1 mol of 12C, are 12.011 amu and 15.9994 amu, respectively.)
Problem 121
Problem 122
A pure titanium cube has an edge length of 2.78 in. How many titanium atoms does it contain? Titanium has a density of 4.50 g/cm3.
Problem 123
A pure copper sphere has a radius of 0.935 in. How many copper atoms does it contain? [The volume of a sphere is (4/3)πr3 and the density of copper is 8.96 g/cm3.]
- What is the radius (in cm) of a pure copper sphere that contains 1.14 * 10^24 copper atoms? [The volume of a sphere is (4/3)πr^3 and the density of copper is 8.96 g/cm^3.]
Problem 124
Problem 125
What is the edge length (in cm) of a titanium cube that contains 2.55 * 1024 titanium atoms? The density of titanium is 4.50 g/cm3.
Problem 126
Boron has only two naturally occurring isotopes. The mass of boron-10 is 10.01294 amu and the mass of boron-11 is 11.00931 amu. Calculate the relative abundances of the two isotopes.
Problem 127
Lithium has only two naturally occurring isotopes. The mass of lithium-6 is 6.01512 amu and the mass of lithium-7 is 7.01601 amu. Calculate the relative abundances of the two isotopes.
Problem 128
Common brass is a copper and zinc alloy containing 37.0% zinc by mass and having a density of 8.48 g/cm3. A fitting composed of common brass has a total volume of 112.5 cm3. How many atoms (copper and zinc) does the fitting contain?
Problem 129
A 67.2 g sample of a gold and palladium alloy contains 2.49×1023 atoms. What is the composition (by mass) of the alloy?
Problem 130
Naturally occurring chlorine is composed of two isotopes: 75.76% Cl-35 (mass 34.9688 amu) and 24.24% Cl-37 (mass 36.9659 amu). Naturally occurring oxygen is composed of three isotopes: 99.757% O-16 (mass 15.9949 amu), 0.038% O-17 (mass 16.9991 amu), and 0.205% O-18 (mass 17.9991 amu). The compound dichlorine monoxide is composed of two chlorine atoms and one oxygen atom bonded together to form the Cl2O molecule. How many Cl2O molecules of different masses naturally exist? Give the masses of the three most abundant Cl2O molecules.
Problem 131
Silver is composed of two naturally occurring isotopes: Ag-107 (51.839%) and Ag-109. The ratio of the masses of the two isotopes is 1.0187. What is the mass of Ag-107?
Problem 132
The U.S. Environmental Protection Agency (EPA) sets limits on healthful levels of air pollutants. The maximum level that the EPA considers safe for lead air pollution is 1.5 µg/m3. If your lungs were filled with air containing this level of lead, how many lead atoms would be in your lungs? (Assume a total lung volume of 5.50 L.)
Problem 133
Pure gold is usually too soft for jewelry, so it is often alloyed with other metals. How many gold atoms are in an 0.255-ounce, 18 K gold bracelet? (18 K gold is 75% gold by mass.)
Problem 153
A volatile liquid (one that easily evaporates) is put into a jar and the jar is then sealed. Does the mass of the sealed jar and its contents change upon the vaporization of the liquid?
Problem 158
Let a triangle represent atoms of element A and a circle represent atoms of element B. b. Draw an atomic view of the compound AB in a liquid state (molecules close together).