a. Complete the following table using the periodic table and your knowldege of electrons.

element	electron configuration	Will (give up or accept)	____ electrons to form a stable octet
Lithium	1s22s1	give up	1
aluminum	1s22s22p63s23p1	give up	3
oxygen	1s22s22p4	accept	2
bromine	1s22s22p63s23p64s23d104p5	accept	1

How did you get those electron numbers? How many will be gained or loss to get a noble gas configuration? Meaning how many to complete the s and p sublevels? How did you know if it would gain or lose? Metals lose, nonmetals gain.

b. Complete the following table using the periodic table and your knowledge of electrons.

compound	metal will give up	charge on metal will become	each chlorine gains _ electrons
RbCl	1	1+	1
SrCl2	2	2+	1
InCl3	3	3+	1
SnCl4*	4	4+	1
SnCl2*	2	2+	1

Wait a minute Mrs Barnwell...what is with the chlorines gaining 1 each time. Note the question - EACH chlorine. And one chlorine gains one electron; that is why you have more than one chlorine in the compound for all but RbCl. The metal is giving away more than one, but chlorine can only accept 1, so you need more 'takers' to make a neutral compound.

* Tin (Sn) has two possible oxidation states, Sn2+ and Sn4+. We will discuss this further in "Naming Compounds". For the purpose of this exercise, know that Sn can form either chloride compound dependent on its oxidation state. The key take-away here is that EACH chlorine may only gain one of the electrons being offered by the cation.

C. Stabillity and Ionic Bonding Questions

1. Noble gases have complete s and p sublevels, so require no changes in number of electrons for stable octets. Other atoms need additional electrons to get valence s and p sublevels complete OR can, in terms or energy, more easily lose outer electrons so that only the full s and p sublevels are the outermost.

2. The octet rule - atoms tend to gain or lose electrons in order to have the outermost s and p sublevels complete - 2 in s and 6 in p. Its relationship to bonding is found by using the octet rule to predict how many electrons element bonding in a compound will gain or lose. This is information will let us see how many of each atom is needed to create a neutral compound.

3. As stabillity increases, energy decreases. An inverse relationship. Its a combination of energies related to losing electrons, gaining electrons and lattice energy.

4. a. Calcium would lose 2

b. oxygen would gain 2

c. iodine gain 1

d. xenon has a stable octet.

5. Magnesium loses 2 electrons. Magnesium could gain six, but the energy related to gaining six is greater than the energy needed to lose 2.

How did you do? Hopefully, you have done well. If not, please study the questions you are unsure of, ask questions in class and in Extra Help and get down these basics. These concepts are fundamental information needed to successful complete future topics. Email me with questions on this assignment!

 

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