Moseley and Atomic Numbers
First Systemization Attempts
Chemists Before Moseley
Modern Periodic Table
Moseley's Experiments
100
the man who numbered the elements
Who is Henry Moseley?
100
published a list of 33 chemical elements, grouping them into gases, metals, nonmetals, and earths
Who is Antoine Lavoisier?
100
wrote the first modern list of elements
Who is Antoine-Laurent de Lavoisier?
100
Dmitri Mendeleev
Who is credited with the first publication of the periodic table?
100
that there were gaps in the atomic number sequence at numbers 43, 61, 72, and 75
What is Moseley's experiment?
200
the number of protons in the nucleus
What are positive charges?
200
observed that many of the elements could be grouped into triads based on their chemical properties; discovered the Law of Triads
Who is Johann Wolfgang Döbereiner?
200
an English chemist who worked on the development of the periodic table
Who is John Newlands?
200
The periodic table
What is a tabular arrangement of the chemical elements?
200
that cobalt and nickel have the different atomic numbers, 27 and 28
What is Moseley's experiments in X-ray spectroscopy?
300
an empirical law concerning the characteristic x-rays that are emitted by atoms
What is Moseley's Law?
300
German chemist who worked with the triad system, and identified ten triads, three groups of four, and one group of five
Who is Leopold Gmelin?
300
credited with the origin of the atom concept
Who is Leucippus and Democritus?
300
The rows of the periodic table
What are periods?
300
a lanthanide or rare earth element
What is element 61?
400
the electron
What is the first sub-atomic particle discovered?
400
a French geologist who published an early form of periodic table. He was the first person to notice the periodicity of the elements.
Who is Alexandre-Emile Béguyer de Chancourtois?
400
credited for the first tables of relative atomic weights
Who is John Dalton?
400
groups
What are the columns of the periodic table?
400
a mixture of two genuine rare-earth elements named neodymium and praseodymium
What is "new twin" and "green twin"?
500
it is a measureable property of the nucleus
What is the K-alpha line of the X-ray spectra of each element?
500
elements could be ordered in the periodic system in order of atomic number rather than atomic weight
What is the contribution of Moseley's x-ray work?
500
a Russian chemist and inventor who formulated the Periodic Law and created his own version of the periodic table of elements
Who is Dmitri Mendeleev?
500
a code for a chemical element
What is a chemical symbol?
500
ion exchange
What is the method of separating the rare-earth elements?
M
e
n
u