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Introduction to Atoms
Organizing the Elements
Metals
Nonmetals and Metalloids
Radioactive Elements
100
John Dalton
What English chemist inferred that atoms had certain characteristics?
100
Its location in the periodic table.
How can the properties of an element be predicted?
100
Move atomic nuclei faster and faster until they have reached very high speeds.
What do particle accelerators do?
100
An element that lacks most of the properties of a metal.
What is a nonmetal?
100
Marie Curie
Who gave radioactivity its name?
200
Its mass number
What identifies an isotope?
200
A state of matter than consists of a gas-like mixture of free electrons and nuclei of atoms that have been stripped of electrons.
What is plasma?
200
When nuclear particles are forced to crash into one another.
How are elements that follow uranium synthesized?
200
Two atoms.
What does a diatomic molecule consist of?
200
French
Of what nationality was scientist Henri Becquerel?
300
As a series of models that developed from experimental evidence.
How did atomic theory grow?
300
Smaller nuclei combine into larger nuclei, creating heavier elements.
What occurs during nuclear fusion?
300
Soft, malleable, shiny metals with high conductivity
What are lanthanides?
300
"Salt forming"
What does the term 'halogens' mean?
300
High energy waves
What does gamma radiation consist of?
400
Energy level
What is an electron's movement related to?
400
Properties of the elements
In the periodic tables used today, ______ repeat in each period-or row- of the table.
400
Shininess, malleability, ductility, and conductivity.
What are some of the physical properties of metal?
400
Their varying ability to conduct electricity.
What is the most useful property of the metalloids?
400
Tracing the steps of chemical reactions and industrial processes, and diagnosing and treating disease.
What do uses of radioactive isotopes include?
500
An atom as consisting of a nucleus that contains protons and neutrons, surrounded by a cloudlike region of moving electrons.
What does a modern atom model describe?
500
He noticed that a pattern of properties appeared when he arranged the elements in order of increasing atomic mass.
How did Mendeleev discover the pattern that led to the periodic table?
500
Alkaline earth metals
What does Group 2 of the periodic table contain?
500
Reactive
What are all of halogens considered very?
500
Photographic film
What has radiation from the uranium-containing mineral exposed as with Becquerel's discovery?