Periodic trends in bonding
Oxygen and Sulfur as specific examples.
1. Read Ch. 21 (963-968; 1001-1004)
2. Review the connection between periodic trends in physical properties (IE, electronegativity, ionic radius, atomic radius) and chemical properties.
kaitlin,
the noble gas notation is the short hand way of writing the spdf notation.
basically you use the noble gas to replace writing out 1s2 2s2 etc.
you use the noble gas (they are in the far right column) thats written before the element you are notating.
ex: you’d use [Ar] for all of period 4 (row 4)
so say you want the noble gas notation for calicum. it would be [Ar] 4s2
hope that helps, laura
Does anyone know all the different topics that will be covered on the exam, because I am studying for but I feel like I am all over the place!
Thanks
MC
IE is the energy change for removing one electron from a gaseous atom. It is always large and positive:
M (g) –> M+ (g) + e- DeltaE = IE
Electron Affinity (EA) is the energy change for adding an electron to a gaseous atom. It is relatively small and negative:
E (g) + e- –> E- (g) DeltaE = EA
The basic idea is that charged species (ions) are really unstable in the gas-phase, as there is nothing to balance the charge. This causes IE to be large and positive, as the product (with two charged species) is at higher energy than the reactant. The EA tends to be small and negative, because it is a comparison between having the charged species being an electron (reactants) or an anion (products).
Sorry I meant for question 3.
Alissa,
For question 2.
Ionization energy is the amount of energy required to remove the outermost electron from 1 mole of atoms / ions, and the electron affinity of an atom or molecule is the amount of energy released in the process.
This would make the two equal in magnitude but their signs would be opposite.
answer to #2: tellurium
answer to #3: as ionization energy increases, electron affinity also increases
Hey, I’m kinda confused on what exactly noble gas notation is…
Does anyone know what we need to know for the differences between sulfur and oxygen?
Hello Olivia,
There is a practice Exam for this upcoming text. Just select the Exam tab. It is under Midterm 2 Topics, with information on the exam and a “practice exam 2”.
Brittany Bausch
answer to # 4 positive means absorbed
Prof. Knapp will there be a practice exam for this upcoming test?
4 exam questions…
1. When energy transitions from level n=4 to n=8, what is the wavelength in nm?
2. Which element has this set of quantum numbers: n = 5, l = 1, m sub l = -1, and m sub s = -1/2?
3. What is the relationship between ionization energy and electron affinity?
4. If the change in enthalpy (H) is positive (+), does that mean energy has been absorbed or evolved?
Knapp, your absence was disappointing. Demos were pretty cool though.
owls are posted friday usually
One thing to remember when writing the ions of the element after you write out the regular notation and take out the part that is the noble gas remember to also take out the first few electrons out of 4s. then follow to 3d if that is needed. it took me a little while to get that so i thought i would share it.
I was having trouble with those as well, but that really cleared it up. Thanks so much!
Nope that wasnt confusing at all!!! thank you for pointing me in the right direction!!!
@Haley
The way I was taught to solve a noble gas notation is by doing the electron configs like you would normally do them. Then look at the noble gas that comes before the element and the atomic number, take the set of electron configs that adds up to the noble gas atomic number and replace it w/ the noble gas and add the rest of the electron config.
eg. Sulfur 16
electron config 1s2 2s2 2p6 3s2 3p4
the noble gas that comes before sulfur is Neon and the atomic # is 10
1s2 2s2 2p6 =10 and replace it with neon then add 3s2 3p4 at the end
[Ne] 3s2 3p4
hope that wasnt confusing
Hey i am having some trouble with the noble gas notation for the electron configs. Does anyone have any helpful tips on how to do this properly?
when are the owls (due sunday night) going to be posted? (i dont have any time to do it this weekend)