This is “End-of-Chapter Material”, section 3.6 from the book Beginning Chemistry (v. 1.0).
This book is licensed under a Creative Commons by-nc-sa 3.0 license. See the license for more details, but that basically means you can share this book as long as you credit the author (but see below), don't make money from it, and do make it available to everyone else under the same terms.
This content was accessible as of December 29, 2012, and it was downloaded then by Andy Schmitz in an effort to preserve the availability of this book.
Normally, the author and publisher would be credited here. However, the publisher has asked for the customary Creative Commons attribution to the original publisher, authors, title, and book URI to be removed. Additionally, per the publisher's request, their name has been removed in some passages. More information is available on this project's attribution page.
For more information on the source of this book, or why it is available for free, please see the project's home page. You can browse or download additional books there. You may also download a PDF copy of this book (40 MB) or just this chapter (2 MB), suitable for printing or most e-readers, or a .zip file containing this book's HTML files (for use in a web browser offline).
How many electrons does it take to make the mass of one proton?
How many protons does it take to make the mass of a neutron?
Dalton’s initial version of the modern atomic theory says that all atoms of the same element are the same. Is this actually correct? Why or why not?
How are atoms of the same element the same? How are atoms of the same element different?
Give complete atomic symbols for the three known isotopes of hydrogen.
A rare isotope of helium has a single neutron in its nucleus. Write the complete atomic symbol of this isotope.
Use its place on the periodic table to determine if indium, In, atomic number 49, is a metal or a nonmetal.
Only a few atoms of astatine, At, atomic number 85, have been detected. On the basis of its position on the periodic table, would you expect it to be a metal or a nonmetal?
Americium-241 is a crucial part of many smoke detectors. How many neutrons are present in its nucleus?
Potassium-40 is a radioactive isotope of potassium that is present in the human body. How many neutrons are present in its nucleus?
Determine the atomic mass of ruthenium from the given abundance and mass data.
Determine the atomic mass of tellurium from the given abundance and mass data.
One atomic mass unit has a mass of 1.6605 × 10−24 g. What is the mass of one atom of sodium?
One atomic mass unit has a mass of 1.6605 × 10−24 g. What is the mass of one atom of uranium?
One atomic mass unit has a mass of 1.6605 × 10−24 g. What is the mass of one molecule of H2O?
One atomic mass unit has a mass of 1.6605 × 10−24 g. What is the mass of one molecule of PF5?
From their positions on the periodic table, will Cu and I form a molecular compound or an ionic compound?
From their positions on the periodic table, will N and S form a molecular compound or an ionic compound?
Mercury is an unusual element in that when it takes a 1+ charge as a cation, it always exists as the diatomic ion.
Propose a formula for hydrogen peroxide, a substance used as a bleaching agent. (Curiously, this compound does not behave as an acid, despite its formula. It behaves more like a classic nonmetal-nonmetal, molecular compound.)
The uranyl cation has the formula UO22+. Propose formulas and names for the ionic compounds between the uranyl cation and F−, SO42−, and PO43−.
The permanganate anion has the formula MnO4−. Propose formulas and names for the ionic compounds between the permanganate ion and K+, Ca2+, and Fe3+.
about 1,800 electrons
It is not strictly correct because of the existence of isotopes.
, , and
It is a metal.
3.817 × 10−23 g
2.991 × 10−23 g
uranyl fluoride, UO2F2; uranyl sulfate, UO2SO4; uranyl phosphate, (UO2)3(PO4)2