Download Oxidation Numbers, Begin Exam Review

Oxidation Numbers, Begin Exam
Review
• Objective
– Today I will be able to:
• Analyze valance electron patterns on the periodic table to assign
oxidation numbers for each family of elements.
• Apply concepts of the periodic table to a review for the exam.
• Evaluation/ Assessment
– Informal assessment –Monitoring students responses as
they complete the periodic table worksheet and exam
review.
– Formal Assessment – Analyzing student responses to the
exit ticket, periodic table worksheet and exam review.
• Common Core Connection
• Build Strong Content Knowledge
• Reason abstractly and quantitatively
• Look for and express regularity in repeated reasoning
Lesson Sequence
• Warm – Up
• Elaborate: Periodic Table Worksheet
– Informal assessment as students answer questions
– Formal assessment collecting responses
– Explain: Oxidation Number Notes
– Elaborate: Exam Review Packet
– Informal assessment as students answer questions
– Formal assessment collecting responses
• Evaluate: Exit ticket
– Formal assessment
Warm - Up
• What are Mendeleev’s contributions to the
periodic table?
• What are Mosley’s contributions to the
periodic table?
• What is periodic law?
Objective
• Today I will be able to:
– Analyze valance electron patterns on the periodic
table to assign oxidation numbers for each family
of elements.
– Apply concepts of the periodic table to a review
for the exam.
Homework
• Complete the Review Packet
• Study for the Periodic Table Exam on
Thursday!
Agenda
•
•
•
•
•
Warm - Up
Review Periodic Table Worksheet
Oxidation Number Notes
Exam Review Packet
Exit Ticket
Periodic Table Worksheet
Review responses to the periodic
table worksheet as a class.
Oxidation Numbers Notes
Oxidation Numbers
• Remember, most atoms strive to have
eight valence electrons
– This is called the Octet Rule
• Atoms will form various bonds by
gaining, losing, or sharing electrons, in
order to satisfy the Octet Rule
Oxidation Numbers
• An atom’s electron configuration is used to
determine how many electrons need to be
gained, lost, or shared
• Example – Na (11 electrons)
• How many valance electrons does sodium have?
– 1 valance electron
• In order for Na to have eight valence electrons,
would it be easier for it to gain 7 electrons, or
lose 1?
– Losing 1 is easier
Oxidation Numbers
• When Na loses an electron it becomes an Na+1
ion
• 1s2 2s2 2p6 3s1 becomes…
• 1s2 2s2 2p6 – 8 valence electrons
• Na carries a +1 charge because it has lost an
electron, and it now has more positively
charged protons than negatively charged
electrons
Oxidation Numbers
• Another Example – Fluorine (9 electrons)
• How many valance electrons does Fluorine
have?
– 7 valance electrons
• In order for F to have eight valence electrons,
would it be easier for it to gain 1 electron, or
lose 7?
– Gaining 1 is easier
Oxidation Numbers
•
•
•
•
When F gains an electron it becomes an F-1 ion
1s2 2s2 2p5 becomes…
1s2 2s2 2p6 – 8 valence electrons
F carries a -1 charge because it has gained an
electron, and it now has more negatively
charged electrons than positively charged
protons
Oxidation Numbers
• There is a fairly consistent pattern to oxidation
numbers with families
• We can assign them in each family going
across
• What would they be for families 1-8?
Oxidation Numbers in Transition
Metals (Side – note)
• Transition Metals and Inner Transition Metals
usually have a varying number of valence
electrons
• Some don’t – Zn+2, Cd+2, Sc+2, Ag+1
Exam Review Packet
Work with the people in your row to
complete the packet. We will review
responses as a class.
Exit Ticket
• What oxidation number is present in the
carbon group?
• Why is this relevant to our next unit of
bonding?