Ch 3 Sec 2 Flashcards
0
Q
Who created the first periodic table? How was it arranged? How is it arranged now? When was it created?
A
- Mendeleev
- by the number of electrons
- arranged now by increasing atomic number
- 1871
1
Q
What is atomic mass?
A
The average mass of all the isotopes of that element.
2
Q
What is periodic table?
A
An arrangement of elements showing the repeating pattern of their property.
3
Q
What is chemical symbol?
A
The abrieboation of the element. It is usually in 1 or 2 letters. Often abrieboation in English but sometimes in Latin.
4
Q
What is periods?
A
It is arranged in rows containing a series of different elements.
5
Q
What is groups?
A
Each column is a group. They are also known as families. They usually have alike chemical properties. (1 reacts violently to water)
6
Q
#periods #goups
A
- 7
* 18
7
Q
Lewis structure
Bohr stricture
A
- outside energy levels
* all energy levels
