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