Question | Answer |
Where did chemists assemble to solve the problems of no way to determine number of atoms in a particular compound or no consistent way to find atomic mass? | 1st international congress of chemists |
presented a method for determining atomic mass | Cannizaro |
included the new values for atomic mass in a textbook he was writing | Mendeleev |
discoverer of periodic law | Mendeleev |
examined the line emission spectra for 38 elements and noticed that elements fit better into patterns when they were arranged according to nucleur charge or the number of protons in the atoms | Moseley |
his work led to defintion of atomic number | Moseley |
states that the physical and chemical properties of the elements are periodic functions of their atomic numbers | Periodic Law |
an arrangement of the elements in order of their atomic number so that elements with similar properties fall in the same column or group | modern periodic table |
discoverer of Radon | Dorn |
additions to the new periodic table: | noble gases, lanthanides, actinides |
added noble gas group to periodic table and discovered the noble gases | Ramsay |
group of 8 electrons filling the highest energy level of an atom | octet |
a unique element with properties that do not match any of those on the periodic table | hydrogen |
group 1 | alkali metals |
silvery metals that are soft enough to be cut with a knife; very reactive; 1 outer shell electron | alkali metals |
group 2 | alkaline earth metals |
harder, denser,stronger than group 1 metals; 2 outer shell electrons | alkaline earth metals |
d-block elements | transition elements |
shiny metals; good conductors | transition elements |
s-block elements together with the p-block elements | main group elements |
shiny 4f metals silimar in reactivity to alkaline earth metals | lanthanides |
5f metals that are all radioactive | actinide |
actinide and lanthanides make up___ | inner transition elements |