The smallest part of an element that is still the element.
What is an atom?
100
Rows on the Periodic Table.
What are periods?
100
The idea of "alchemy" ended and the scientific method began to develop.
What occurred during the 1860's?
100
A combination of two or more substances that are not chemically combined.
What is a mixture?
200
A change in matter's appearance. However, the matter's identity does not change.
What is a physical change?
200
The theory that atoms have three subatomic particles, a nucleus, and an electron cloud.
What is the Modern Theory of Atoms?
200
Columns on the Periodic Table.
What are groups?
200
About sixty elements.
How many elements were known during the 1860's?
200
A substance made up of atoms or ions of two or more different elements joined by chemical bonds.
What is a compound?
300
A change in the identity of matter.
What is a chemical change?
300
The number of protons that an atom contains.
What determines an atom's atomic number?
300
These elements have similar chemical and physical properties.
How are elements in groups related?
300
A Russian chemist who was the original creator of the Periodic Table.
Who was Dmitri Mendeleev?
300
Bond where electrons are gained or lost.
What is an ionic bond?
400
A phase change where energy is consumed.
What is an endothermic phase change?
400
The number of protons and neutrons that an atom contains.
What determines an atom's atomic mass?
400
The most abundant type of element on the Periodic table, these elements are left of the zigzag line. In general, they have few valence electrons and are solid at room temperature, shiny, ductile, conductive, and malleable.
What are metals?
400
Mendeleev put element names and properties on cards, then arranged the cards like solitaire. He also used elements' atomic masses to determine their order on the Periodic Table.
How did Dmitri Mendeleev organize the Periodic Table?
400
Bond that forms when atoms share one or more pairs of electrons.
What is a covalent bond?
500
The second to last label on a heating curve.
What is vaporization?
500
It can contain up to two valence electrons.
How many valence electrons can atoms' first energy levels contain?
500
The least abundant type of elements on the Periodic Table, these elements border the zigzag line and have certain properties of metals and certain properties of nonmetals.
What are metalloids?
500
A British scientist who improved the accuracy of the Periodic Table by arranging elements by their atomic numbers as opposed to their atomic masses.
Who was Henry Moseley?
500
Bond that is formed by the attraction between positively charged metal ions and the electrons around them.