Concept explainers
Neutron stars are believed to be composed of solid nuclear matter, primarily neutrons.
a. If the radius of a neutron is
b. Assuming that a neutron star has the same density as a neutron, calculate the mass in kilograms of a small piece of a neutron star the size of a spherical pebble with a radius of 0. 10 mm.
Want to see the full answer?
Check out a sample textbook solutionChapter 4 Solutions
Mastering Chemistry MyLab CHM 1025
- Average Atomic Weight Part 1: Consider the four identical spheres below, each with a mass of 2.00 g. Calculate the average mass of a sphere in this sample. Part 2: Now consider a sample that consists of four spheres, each with a different mass: blue mass is 2.00 g, red mass is 1.75 g, green mass is 3.00 g, and yellow mass is 1.25 g. a Calculate the average mass of a sphere in this sample. b How does the average mass for a sphere in this sample compare with the average mass of the sample that consisted just of the blue spheres? How can such different samples have their averages turn out the way they did? Part 3: Consider two jars. One jar contains 100 blue spheres, and the other jar contains 25 each of red, blue, green, and yellow colors mixed together. a If you were to remove 50 blue spheres from the jar containing just the blue spheres, what would be the total mass of spheres left in the jar? (Note that the masses of the spheres are given in Part 2.) b If you were to remove 50 spheres from the jar containing the mixture (assume you get a representative distribution of colors), what would be the total mass of spheres left in the jar? c In the case of the mixture of spheres, does the average mass of the spheres necessarily represent the mass of an individual sphere in the sample? d If you had 80.0 grams of spheres from the blue sample, how many spheres would you have? e If you had 60.0 grams of spheres from the mixed-color sample, how many spheres would you have? What assumption did you make about your sample when performing this calculation? Part 4: Consider a sample that consists of three green spheres and one blue sphere. The green mass is 3.00 g, and the blue mass is 1.00 g. a Calculate the fractional abundance of each sphere in the sample. b Use the fractional abundance to calculate the average mass of the spheres in this sample. c How are the ideas developed in this Concept Exploration related to the atomic weights of the elements?arrow_forwardYou perform a chemical reaction using the hypothetical elements A and B. These elements are represented by their molecular models shown below: The product of the reaction represented by molecular models is a Using the molecular models and the boxes, present a balanced chemical equation for the reaction of elements A and B. b Using the symbols A and B2 for the chemical reaction, write a balanced chemical equation. c What are some real-element possibilities for element B?arrow_forwardCopper atoms. (a) What is the average mass of one copper atom? (b) Students in a college computer science class once sued the college because they were asked to calculate the cost of one atom and could not do it. But you are in a chemistry course, and you can do this. (See E. Felsenthal, Wall Street Journal, May 9, 1995.) If the cost of 2.0-mm diameter copper wire (99.9995% pure] is currently 41.70 for 7.0 g, what is the cost of one copper atom?arrow_forward
- 2.92 A candy manufacturer makes chocolate-covered cherries. Although all of the products look roughly the same, 3% of them are missing the cherry. The mass of the candy with a cherry is 18.5 g; those missing the cherry weigh only 6.4 g. (a) How would you compute the average mass of a box of 100 of these chocolate covered cherries from this manufacturer? (b) I low is this question analogous to the determination of atomic weights?arrow_forwardIn a neutron star, gravity causes the electrons to combine with protons to form neutrons. A typical neutron star has a mass half that of the sun, compressed into a sphere of radius 20 km. If such a neutron star contains 6.01056 neutrons, calculate its density in grams per cubic centimeter. Compare this with the density inside a 232Th nucleus, in which 142 neutrons and 90 protons occupy a sphere of radius 9.11013cm . Take the mass of a neutron to be 1.6751024g and that of a proton to be 1.6731024g .arrow_forwardA materials engineer has filed for a patent for a new alloy to be used in golf club heads. The composition by mass ranges from 25 to 31% manganese, 6.3 to 7.8% aluminum, 0.65 to 0.85% carbon, and 5.5 to 9.0% chromium, with the remainder being iron. What are the maximum and minimum percentages of iron possible in this alloy? Use Figure 2.12 to snake a prediction about how the density of this alloy would compare with that of iron; justify your prediction.arrow_forward
- Two elements, R and Q, combine to form two binary compounds. In the first compound, 14.0 g of R combines with 3.00 g of Q. In the second compound, 7.00 g of R combines with 4.50 g of Q. Show that these data are in accord with the law of multiple proportions. If the formula of the second compound is RQ, what is the formula of the first compound?arrow_forward2.95 Engineers who design bicycle frames are familiar with the densities of aluminium (2.699 g/cm3), steel (7.87 g/cm3), and titanium (4.507 g/cm3). How does this information compare with Figure 2.12, and what would it suggest for changes in this figure if more shades were used for the density colour-coding? (Iron is the principal component of steel)arrow_forwardNeon has three stable isotopes, one with a small abundance. What are the abundances of the other two isotopes? 20Ne, mass = 19.992435 u; percent abundance = ? 21Ne mass = 20.993843 u; percent abundance = 027% 22Ne mass = 21.991383 u: percent abundance = ?arrow_forward
- The photo here depicts what happens when a coil of magnesium ribbon and a few calcium chips are placed in water. (a) Based on these observations, what might you expect to see when barium, another Croup 2A element, is placed in water? (b) Give the period in which each element (Mg. Ca, and Ba) is found. What correlation do you think you might find between the reactivity of these elements and their positions in the periodic table?arrow_forwardThere are 2.619 1022 atoms in 1.000 g of sodium. Assume that sodium atoms are spheres of radius 1.86 and that they are lined up side by side. How many miles in length is the line of sodium atoms?arrow_forwardWhen mixtures of gaseous H2 and gaseous Cl2 react, a product forms that has the same properties regardless of the relative amounts of H2 and Cl2 used. a. How is this result interpreted in terms of the law of definite proportion? b. When a volume of H2 reacts with an equal volume of Cl2 at the same temperature and pressure, what volume of product having the formula HCI is formed?arrow_forward
- Principles of Modern ChemistryChemistryISBN:9781305079113Author:David W. Oxtoby, H. Pat Gillis, Laurie J. ButlerPublisher:Cengage LearningChemistry: An Atoms First ApproachChemistryISBN:9781305079243Author:Steven S. Zumdahl, Susan A. ZumdahlPublisher:Cengage LearningChemistry: The Molecular ScienceChemistryISBN:9781285199047Author:John W. Moore, Conrad L. StanitskiPublisher:Cengage Learning
- Chemistry & Chemical ReactivityChemistryISBN:9781337399074Author:John C. Kotz, Paul M. Treichel, John Townsend, David TreichelPublisher:Cengage LearningChemistry: Principles and ReactionsChemistryISBN:9781305079373Author:William L. Masterton, Cecile N. HurleyPublisher:Cengage LearningChemistry for Engineering StudentsChemistryISBN:9781337398909Author:Lawrence S. Brown, Tom HolmePublisher:Cengage Learning