Module 3 Valence Electrons - Journal 03.01

How many electrons are in the valence shell of noble gases?

8

Electronegativity

A measure of the ability of an atom in a chemical compound to attract electrons

Describe the pattern for the other tall columns.

Across the period from left to right - each group down a column holds the same amount of valence electrons - gaining an electron each group.

How does ionization energy determine the bonding behavior of an element?

An element with a low ionization energy will react readily by losing its outer electron. Ionization energy is measured for the successive removal of each electron of an atom. - If it has low ionization energy it will easily give up its valence electron to an element with higher ionization energy.

How does electronegativity determine the bonding behavior of an element?

Electronegativity is the measure of how strongly an atom pulls its bonding pair of electrons towards itself. ... The four valence electrons that the hydrogen and oxygen atoms share are more attracted to (or spends more time with) the oxygen atom; this is because oxygen is more electronegative.

valence electrons

Electrons on the outermost energy level of an atom

How many outer shell electrons are in the first group on the periodic table?

Elements in the first group of the periodic table have just one electron in their outer shell.

Reactivity of Chlorine—group 7:

Group 7 elements are less reactive down the group because the electron shells have a repulsive effect on the reacting electron, which weakens the force of electrostatic attraction between it and the positive nucleus.

Describe what you learned about valence electrons for each group of the periodic table.

Groups 1: have one 1 valence electron Group 2: has 2 valence electrons Transition metals vary Groups 3-7 3 has 3 and so on Group 8 noble gases have 8

What did Lewis's octet rule propose?

He proposed that a sharing of two electrons by two hydrogen atoms permits each one to have a stable closed-shell electron configuration analogue to helium. ... Helium is an exception; the two electrons are shown as a pair. For molecules, before we draw their Lewis structures we have to learn octet rule.

What is the different between ionic and covalent bonds?

Ionic bonds transfer electrons, and covalent share electrons.

Why are valence electrons mostly found in the s and p sublevels of the outermost energy level in an atom?

Only electrons in the s and p orbitals are valance electrons, so a given atom can have between 0 and 7 valance electrons. Atoms with 0 valence electrons are called noble gases and don t like form bonds.

ionization energy

The amount of energy required to remove an electron from an atom

Explain how position on the periodic table relates to an element's reactivity.

The farther to the left and down the periodic chart you go, the easier it is for electrons to be given or taken away, resulting in higher reactivity. Period - reactivity increases as you go from the left to the right across a period. Group - reactivity decreases as you go down the group.

The greater the difference in electronegativity

The greater the difference in electronegativity, the more polarized the electron distribution and the larger the partial charges of the atoms.

Why do scientists use noble gas configurations to represent valence electrons?

The noble gas shorthand is used to summarize the electron configuration of an element while providing the most relevant information about the valence electrons of that element. The noble gas is substituted to represent all of the electrons that aren't valence electrons.

How do an element's valence electrons relate to its chemical reactivity?

The number of the electrons in the shell

How are valence electrons identified in electron configurations?

The ones digit in the group number is the number of valence electrons. To solve without a periodic table, find the electron configuration of the element and count the electrons into 1 group of 2, and then into shells of 8. The number in the last group is the amount of valence electrons.

How are Lewis dot structures used to illustrate valence electrons?

Valence electronic structures can be visualized by drawing Lewis symbols (for atoms and monatomic ions) . Lone pairs, unpaired electrons, and single, double, or triple bonds are used to indicate where the valence electrons are located around the atom.

Explain the relationship between valence electrons and bonding.

Valence electrons attract each other, they also either want to transfer between molecules or share between molecules.

What is the benefit of using Lewis dot structures to represent valence electrons?

You are able to see lone pairs, bonded pairs and in their single, double, triple bonding in an easy way.

ionic bonding

a chemical bond that results from the electrostatic attraction between positive and negative ions. This means that in an ionic bond, electrons are given up by one atom and gained by another atom, and then those atoms are attracted to each other.

octet rule

atoms react by gaining or losing electrons so as to acquire the stable electron structure of a noble gas, usually eight valence electrons

Combine lithium and neon. Why don't they bond together?

because neon is a noble gas with a full valence shell

Why are transition metals more "eager" to react with substances than transition metals to the right of the periodic table?

cause they have seven valence electrons

How do valence electrons affect the bonding properties of elements?

depending on valence electrons this determines what you can bond with or if you can bond

covalent bonding

electrons are shared between two atoms, neither atom completely gaining or losing electrons. Because atoms in covalent bonds overlap their outer energy levels, both atoms "own" the shared electrons.

The atoms of elements can lose, gain, or even share _______. How many are needed for stable configurations?

electrons; 8

transition metals

groups 3-12 variations on valence electrons

The outermost shell is the ____ energy level that contains ___ in an atom.

highest; electrons

Reactivity of Sodium—group 1:

highly reactive and is never found pure in nature.

If the valence electrons equal eight, the element is ________. What does this mean regarding reactivity?

noble gas (full); low chemical reactivity

how do you create a noble gas notation to represent the valence electrons of an element.

spdf Each s energy level can hold a maximum of 2 electrons. Each p energy level can hold a maximum of 6 electrons. Each d energy level can hold a maximum of 10 electrons. Each f energy level can hold a maximum of 14 electrons.

What shorthand notations are used to illustrate valence electrons?

spdf - noble gas confirgurations

How is the periodic table used to determine an element's valence electrons?

tall columns across a period gain one for each group. alkali metals are 1 to noble gases 8. (transition metals have different ways of determining valence electrons)

chemical bond

the attractive force that holds atoms or ions together

Combine hydrogen and fluorine. Describe how they bond.

they share an electron each. covalently

Reactivity of Carbon—group 4:

weakly reactive

octet rule exceptions

-Hydrogen (has only 2) -Lithium, Beryllium, and boron (less than 8) -all period 3 and below can hold >8