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