A) their masses are always equal. B) their volumes are always equal. C) the ratio of their masses is always the same. D) each element contributes an equal number of atoms.
A) Negative and positive charges are spread evenly throughout an atom. B) Alpha particles have a positive charge. C) There is a dense, positively charged mass in the center of an atom. D) Gold is not as dense as previously thought.
A) concentrated at multiple sites in an atom. B) located in the space outside the nucleus. C) spread evenly throughout an atom. D) concentrated in the center of an atom.
A) proton B) electron C) neutron
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 number of neutrons B) the number of protons C) the charge on the electrons D) the mass of the neutron
A) isotope B) charge C) mass number D) atomic number
A) isotope number from atomic number B) mass number from atomic number C) atomic number from electron number D) atomic number from mass number
A) like popcorn in a popper. B) like planets orbiting the sun. C) like balls rolling down a hill. D) like beach balls on water waves.
A) the mass of the electrons in the atom B) the most likely locations of electrons in an atom C) the number of electrons in an atom D) the precise location of electrons in an atom
A) they are usually gases B) the are extremely nonreactive C) they are located in the left-most column of the periodic table D) they form negative ions
A) amount of a substance B) electric charge of a substance C) mass of a substance D) volume of a substance
A) atomic number B) mass number C) atomic mass unit D) isotope number
A) its atomic mass B) the ratio of protons to neutrons in atoms of the element C) how tightly atoms are packed in the element D) the number of valence electrons in atoms of the element
A) their masses are identical B) They have the same mass number C) They are isotopes of oxygen D) they do not have the same number of protons
A) group to group B) column to column C) row to row D) element to element
A) helium, carbon, gold B) phosphorus, nitrogen, oxygen C) iodine, iron, nickel D) sodium, chromium, copper
A) the discovery of elements with predicted properties. B) the discovery of the nucleus. C) the immediate acceptance by other scientists. D) the discovery of subatomic particles.
A) four B) two C) three D) none
A) decreases B) increases then decreases C) stays the same D) increases
A) chlorine-35 atom B) neutron C) carbon-12 atom D) proton
A) 0 B) -1 C) +1 D) -2
A) 1/18 B) 0 C) 1/1840 D) 1
A) number of neutrons B) period C) chemical properties D) mass
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-twelfth the mass of a carbon-12 atom B) one-fifteenth the mass of a nitrogen-15 atom C) one-fourth the mass of a lithium atom D) one-half the mass of a hydrogen atom
A) they can form compounds with bright colors B) They exist as single elements rather than molecules C) they are rare in nature D) they are highly reactive
A) are extremely hard B) can conduct electric current only under certain conditions C) do not form compounds D) have large atomic masses but small atomic numbers
A) on the left B) in the middle C) on the right D) on the bottom
A) one mole of a pure substance B) one kilogram of a pure substance. C) one liter of a pure substance D) one gram of a pure substance
A) 79 B) 80 C) 35 D) 172
|