Periodic Table
Classifying Elements
Periodic Table History
Representative Elements
Transition Elements
100
Elements that are gases or brittle solids and poor conductors of heat and electricity.
What is Nonmetals?
100
A gas at room temperature.
What is nonmetal?
100
Many different elements had been isolated and named by 1830.
What is 55?
100
Groups 1 and 2 are metals found in nature combined with other elements.
What is active metals?
100
These elements are metals;most are combined with other elements in ores.
What is transition elements?
200
Basis for arranging elements in modern periodic table.
What is atomic number?
200
A poor conductor of electricity.
What is nonmetal?
200
In 1869, this scientist arranged elements in order of increasing mass and found that elements with similar properties fell into groups.
What is Mendeleev?
200
Silvery solids with low densities and low melting points; they increase in reactivity from top to bottom of the periodic table.
What is alkali metals?
200
Several transition elements can be used as substances that make a reaction occur faster.
What is catalysts?
300
Elements that show properties of both metals and nonmetals.
What is metalloids?
300
Can be used as a semiconductor.
What is metalloid?
300
This scientist improved the periodic table by arranging the elements according to atomic number instead of atomic mass.
What is Moseley?
300
These metals are denser, harder, have higher melting points, and are slightly less active than alkali metals in the same period.
What is alkaline earth metals?
300
The inner transition elements.
What is lanthanides and actinides?
400
Group of elements that form salts.
What is halogens?
400
Can be hammered into thin sheets.
What is metal?
400
This term was assigned to identify groups 1 and 2 along with Groups 13 and 18.
What is representative elements?
400
This element is found in all living things and exists in several forms.
What is carbon?
400
Soft metals once thought to be rare.
What is lanthanides?
500
Most elements fall into this classification.
What is metals?
500
Can be drawn out into a thin wire.
What is metal?
500
Groups 3 and 12 are identified with this term.
What is transition elements?
500
These elements rarely combine with other elements, they are often used in lighting and inflating balloons.
What is noble gases?
500
These elements are radioactive; several are synthetic elements that do not occur naturally.
What is actinides?
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