A) each element contributes an equal number of atoms. B) their volumes are always equal. C) their masses are always equal. D) the ratio of their masses is always the same.
A) Negative and positive charges are spread evenly throughout an atom. B) Alpha particles have a positive charge. C) Gold is not as dense as previously thought. D) There is a dense, positively charged mass in the center of an atom.
A) concentrated at multiple sites in an atom. B) located in the space outside the nucleus. C) concentrated in the center of an atom. D) spread evenly throughout an atom.
A) proton B) neutron C) electron
A) Unlike protons or neutrons, electrons have no mass. B) Neutrons have no charge and no mass. C) An electron has far less mass then either a proton or a neutron. D) Protons, neutrons, and electrons all have about the same mass.
A) the mass of the neutron B) the charge on the electrons C) the number of protons D) the number of neutrons
A) isotope B) charge C) mass number D) atomic number
A) isotope number from atomic number B) atomic number from mass number C) atomic number from electron number D) mass number from atomic number
A) like beach balls on water waves. B) like planets orbiting the sun. C) like balls rolling down a hill. D) like popcorn in a popper.
A) the precise location of electrons in an atom B) the number of electrons in an atom C) the most likely locations of electrons in an atom D) the mass of the electrons in the atom
A) they form negative ions B) they are usually gases C) they are located in the left-most column of the periodic table D) the are extremely nonreactive
A) electric charge of a substance B) mass of a substance C) amount of a substance D) volume of a substance
A) isotope number B) atomic mass unit C) mass number D) atomic number
A) how tightly atoms are packed in the element B) its atomic mass C) the number of valence electrons in atoms of the element D) the ratio of protons to neutrons in atoms of the element
A) They have the same mass number B) They are isotopes of oxygen C) they do not have the same number of protons D) their masses are identical
A) column to column B) group to group C) row to row D) element to element
A) sodium, chromium, copper B) helium, carbon, gold C) phosphorus, nitrogen, oxygen D) iodine, iron, nickel
A) the discovery of the nucleus. B) the immediate acceptance by other scientists. C) the discovery of subatomic particles. D) the discovery of elements with predicted properties.
A) two B) three C) four D) none
A) increases B) stays the same C) decreases D) increases then decreases
A) carbon-12 atom B) proton C) neutron D) chlorine-35 atom
A) +1 B) 0 C) -1 D) -2
A) 1 B) 0 C) 1/1840 D) 1/18
A) mass B) period C) chemical properties D) number of neutrons
A) changing from lithium into fluorine B) losing or gaining protons C) changing from one period to another D) losing or gaining electrons
A) one-fifteenth the mass of a nitrogen-15 atom B) one-twelfth the mass of a carbon-12 atom C) one-fourth the mass of a lithium atom D) one-half the mass of a hydrogen atom
A) they are highly reactive B) They exist as single elements rather than molecules C) they can form compounds with bright colors D) they are rare in nature
A) can conduct electric current only under certain conditions B) are extremely hard C) have large atomic masses but small atomic numbers D) do not form compounds
A) on the left B) in the middle C) on the right D) on the bottom
A) one kilogram of a pure substance. B) one liter of a pure substance C) one gram of a pure substance D) one mole of a pure substance
A) 80 B) 35 C) 172 D) 79
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