Critical Vocabulary- Chemistry

Front 1

Neutral Atom

Back 1

Atom that has the same number of protons as electrons.
All elements on periodic table are neutral.
Ex: BE (Beryllium) 4 protons= 4 electrons

Front 2

Atom

Back 2

atoms are what matter is composed of, or smallest component of an element having the chemical properties of the element

Front 3

Atomic Mass

Back 3

Atomic mass - The average mass of one atom of an element.
Some example -
Calcium is 40.1
Strontium is 87.6

Front 4

Atomic Number

Back 4

Atomic Number:
The average mass of one atom of and element.
Example: Titanium- 47.88

Front 5

Chemistry

Back 5

The science that deals with the composition and properties of substances and various elementary forms of matter.

ex: Periodic Table of Elements

Front 6

Dmitri Mendeleev

Back 6

Russian scientist that made the first periodic table in 1869

Front 7

Electron Configuration

Back 7

The arrangement of the electrons in the shells of the atom, or in other words, the energy levels

Front 8

electron shell

Back 8

the levels of electrons in an atom
ex: Carbon has 2 electron shells. a K shell and L shell.

Front 9

Element

Back 9

Any of the more than 100 known substances (of which 92 occur naturally) that cannot be separated into simpler substances and that singly or in combination constitute all matter

Front 10

Group/family

Back 10

The columns going down is the family and they get increase reactivity from left to right. The horizontal rows represents groups which can show how stable an atom is.

Front 11

Ion

Back 11

An ion is an atom or molecule that has gained or lost valence electrons, giving it a positive or negative charge.

Example:He2- is a positive ion because it has lost 2 valence electrons to become stable.

Front 12

Isotope

Back 12

Isotope:
An atom with the same number of protons and different number of neutrons fron other atoms of the same element.

Examples: Non isotope of Cobalt- 27 protons and 32 neutrons

Front 13

Metalloids

Back 13

Chemical elements that share properties of both metals and non-metals

Front 14

Neils Bohr

Back 14

Neils Henrik David Bohr was a danish physicist who made fundamental contributions to understanding atomic structure. He is also responsible for creating the Bohr Model, a model which shows representations of electrons their and shells.

Front 15

Neutron

Back 15

A subatomic particle that is located in the nucleus of the atom. It is also used to calculate the atomic mass of the atom.It has neutral charge, and therefore doesn't have a large effect on the atom's properties.

Front 16

nucleus

Back 16

The center of an atom, containing the protons and neutrons. the nucleus contains much of the atomic mass, usually almost all.

Front 17

octet

Back 17

8 valence electrons in an atom
ex: Noble gases are all octets. they all have 8 valence electrons

Front 18

Period

Back 18

A horizontal row of elements in the periodic table.

Front 19

Physical Property

Back 19

-A property that can be measured without changing the chemical compostition of a substance.

Ex:color-red, shape-round

Front 20

Stable Atom

Back 20

An atom has a full outer shell.

Front 21

The Periodic Table

Back 21

The Periodic Table was initialy founded by Dimitri Mendeleev. The table tells a lot about an element. It is in order by atomic number. elements in a column are called a family. Elements that are horizontal to each other are called a period. Elements in the same family all have the same number of valance electrons. Elements in the same period all have the same number of electron shells

Front 22

Valence Electrons

Back 22

Valence Electrons:
The Valence electron are the electrons in the last shell or energy level of an atom. When you move from left to right on a periodic table the number of Valence electrons increase, and decrease from right to left.