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