A gold atom has a diameter of 2.88 × 10210 m. Suppose the atoms in 1.00 mol of gold atoms are arranged just touching their neighbors in a single straight line. Determine the length of the line.

The density of gold, Au, is 19.32 g/cm3. What is the volume (in cubic centimeters) of a piece of gold that contains 2.6 × 1024 atoms?

The early alchemists used to do an experiment in which water was boiled for several days in a sealed glass container. Eventually. some solid residue would appear in die bottom of the flask, which was interpreted to mean that some of the water in the flask had been converted into earth. When Lavoisier repeated this experiment, he found that the water weighed the same before and after heating, and the mass of die flask plus the solid residue equaled the original mass of the flask. Were the alchemists correct? Explain what really happened. (This experiment is described in the article by A. F. Scott in Scientific American, January 1984.)

The density of a mixture of gases may be calculated by summing the products of the density of each gas and the fractional volume of space occupied by that gas. (Note the similarity to the calculation of the molar mass of an element from the isotopic masses and fractional abundances.) Assume dry air with CO2 removed is 20.96% (by volume) oxygen. 78.11% nitrogen, and 0.930% argon. Determine the density of argon.

There are 1.699 1022 atoms in 1.000 g of chlorine. Assume that chlorine atoms are spheres of radius 0.99 and that they are lined up side by side in a 0.5-g sample. How many miles in length is the line of chlorine atoms in the sample?

3.80 Which one of the following metal samples cannot possibly exist? not? (a) a piece of gold foil 10-6 m thick (b) 5 mg of platinum (c) 10-24 mol of aluminum (d) a copper wire 0.1 mm in diameter

In 1886 Eugene Goldstein observed positively charged particles moving in the opposite direction to electrons in a cathode ray tube (illustrated below). From their mass, he concluded that these particles were formed from residual gas in the tube. For example, if the cathode ray tube contained helium, the canal rays consisted of He+ ions. Describe a process that could lead to these ions. Canal rays. In 1886, Eugene Goldstein detected a stream of particles traveling in the direction opposite to that of the negatively charged cathode rays (electrons). He called this stream of positive particles "canal rays:"

he vigorous reaction between aluminum and iodine gives the balanced equation: :math>2Al(s)+3I2(s)2AlI2(s). mg src=Images/HTML_99425-9-2QAP_image001.jpg alt="" align="top"/> at do the coefficients in this balanced chemical equation tell us about the proportions in which these substances react on a macroscopic (mole) basis?

Reference Section 5-2 to find the atomic masses of 12C and 13C, the relative abundance of 12C and 13C in natural carbon, and the average mass (in u) of a carbon atom. If you had a sample of natural carbon containing exactly 10,000 atoms, determine the number of 12C and 13C atoms present. What would be the average mass (in u) and the total mass (in u) of the carbon atoms in this 10,000-atom sample? If you had a sample of natural carbon containing 6.0221 1023 atoms, determine the number of 12C and 13C atoms present What would be the average mass (in u) and the total mass (in u) of this 6.0221 1023 atom sample? Given that 1 g = 6.0221 1023 u, what is the total mass of I mole of natural carbon in units of grams?

A sample of solid elemental phosphorus that is deep red in color is burned. While the phosphorus is burning, a white smoke is produced that is actually a finely divided solid that is collected. a. Have the molecules of phosphorus been changed by the process of burning? Explain your answer. b. Is the collected white solid a different substance from the phosphorus? Explain you answer. c. In terms of the number of atoms contained, how do you think the size of the molecules of the white solid compares with the size of the molecules of phosphorus? Explain your answer. d. Classify molecules of the collected white solid using the term homotatomic or heteroatomic. Explain your reasoning.