periods and groups Flashcards
1
Q
what is a period
A
Horizontal rows
2
Q
how many period are there
A
7
3
Q
what does the periods tell you
A
Indicate the electron shell an element is in
- If an element was in period 7, it would have seven shells etc.
4
Q
what are groups
A
vertical columns
5
Q
how are the periods numbered
A
top to bottom
6
Q
how are the groups numbered
A
left to right
7
Q
what do elements in the same group have in common
A
they have similar chemical properties
8
Q
what do the groups represent
A
Indicate how many valence electrons (outer most) there is in the element. for example, magnesium is in group two, therefore it has two electrons in its valence shell
9
Q
what is another name for group 1
A
alkali metals
10
Q
what is another name for group 2
A
alkaline earth metals
11
Q
what is another name for group 17
A
halogens
12
Q
A
