Valence Electrons
Valence Electrons are found where?
In the highest occupied energy level
A negative ion
Anion
What group do lithium and potassium belong to? Give me the name of the group, not a number
alkali metals
What period is an element with this electron configuration: 1s2 2s2 3p6
Period: 3
O-
1s2 2s2 2p5
The number of Valence Electrons in group 2 elements is _____
2
A positive ion
cation
Elements in the same group have similar
properties
What group is an element in with this electron configuration: 1s2 2s2 3p6 3s2 3d4
Group 6
K+
1s2 2s2 2p6 3s2 3p6
Bromine, atomic number 35, belongs to Group 17. How many valence electrons does bromine have?
7
The measure of an atom to attract electrons is called
Electronegativity
as you move left to right on the periodic table, what happens to the atomic radii
decrease
The electron configuration of an element is [Ne] 3s2 3p3. This element is in period
Period 3
O2-
1s2 2s2 2p6
How many valence electrons does Lead (Pb) have?
4
Arrange the following elements in order of decreasing electron affinity: C, O, Li, Na, Rb, and F
F, O, C, Li, Na, Rb
Compared to the alkali metals, the alkaline-earth metals
are less reactive
The electron configuration of an element is [Kr] 4d6 5s1. To what group does this element belong
Group 7
Mg 3+
1s2 2s2 2p5
Ar, Cl, Na, Al: Order these from the least to most valence electrons
Na, Al, Cl, Ar
How does the size of an anion compare with its neutral atom?
It is larger because more electrons = more negative charge, and the nucleus cannot pull them closer effectively
Why are halogens extremely reactive
They have 7 valence electrons, which are one short of an octet, this means that they want to get one more electron, and will react with a wide variety of elements to do so
[Ne] 3s2 3p6 Based on this electron configuration, what is the period, group, element, and element type?
Period: 3
Group: 18
Element: Argon
Element type: Noble Gas
Will Cl lose or gain electrons? What is the ion most likely to be formed and what is the noble gas that will be achieved?
Cl will gain 1 electron (Cl-) Noble gas = Argon (Ar)