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