Past Chem Content Review
What is electronegativity?
The ability of an atom in a bond to attract electrons
Define "intermolecular forces" and "intramolecular forces". What is the difference?
Intermolecular = between different molecules
Intramolecular = between one molecule
Explain the "rule of zero charge"
The overall positive charge and the overall negative charge in an ionic compound must cancel out to zero charge overall.
Why does the "sea of electrons" form in a metallic bond?
The sea of electrons form because electrons are delocalized- all nuclei of the metals don't have a super strong pull on the electrons so they all float between the different metal atoms.
What year did Ms. DeCotis graduate from CCA?
2020
Why do elements react with each other?
They want to become stable (have a full outer valence shell of electrons)
What type of compound is CH4? What properties would this compound have? (Name at least 2)
Covalent compound
- Low melting/ boiling point
- Poor conductor of electricity
- Can be gas, liquid, or solid
- Soft and flexible
What is the name of MgBr?
Magnesium Bromide
What is the difference between a metallic bond, an ionic bond, and a covalent bond?
Metallic bond = metal-metal, electrons are delocalized
Ionic bond = metal-nonmetal, electrons are transferred (lost/ given)
Covalent bond = nonmetal-nonmetal, electrons are shared
Where did Ms. DeCotis go to college?
Tufts University
What is the difference between a chemical reaction and a nuclear reaction?
Nuclear - number of protons changes, happens in the nucleus
Chemical - number of electrons changes, happens in the electron cloud
What type of ion would sulfur form? What would the oxidation number be and how would it like to bond?
Sulfur would form an anion because it wants to gain 2 electrons. Oxidation number = -2.
Write the formula for iron (III) oxide
Fe2O3
What does it mean for electrons to be delocalized?
Electrons are not localized to one specific atom, they can freely move between electron clouds of atoms
What did Ms. DeCotis do her senior thesis on?
A. How Snoop Dogg and Martha Stewart's Friendship Will Impact Climate Change
B. Boycotting the Meat Industry to Stop Deforestation in the Amazon
C. The Ethics of the Fast Fashion Industry: Why Shopping Sustainably is Best
D. A Classical Christian Education is the Best Academic Environment
B. Boycotting the Meat Industry to Stop Deforestation in the Amazon
Draw
1) a picture of a bond with a change in electronegativity > 2
2) a picture of a bond with a change in electronegativity < 2
1) Ionic
2) Covalent
DAILY DOUBLE
Which compound has the least ionic character and which compound has the greatest ionic character?
A. LiF
B. NiBr2
C. CO2
D. N2
Which compound do we not know how to name thus far? Why?
A. Na2CO3
B. SCl2
C. NH4Cl
D. CaO
We do not know how to name SCl2 yet because it is a covalent compound (and we have not covered naming covalent compounds yet)
Name 3 properties of metals that result from metallic bonds
1. Ductile
2. Good conductor of electricity/ heat
3. Malleable
4. High melting point
5. Shiny
What is the name of Ms. DeCotis' youngest sister?
Ava
Write the electron configuration of a sodium ion?
Ion = lost/gained electrons
Na+: 1s22s22p6
Na+: [He]2s22p6
Use Lewis structures to draw the
1) bond that forms between magnesium and chlorine. What type of bond is this?
2) bond that forms between carbon and oxygen. What type of bond is this?
MgCl2 - ionic
CO2 - covalent
What is the chemical formula for ammonium sulfate?
(NH4)2SO4
Draw a picture of a metallic bond
Sea of electrons
DAILY DOUBLE
What sport does Ms. DeCotis play at least 3 times a week year-round?