Quiz 3 Flashcards
Name the seven most important diatomic elements?
Hydrogen Nitrogen Oxygen Fluorine Chlorine Bromine Iodine
What are diatomic molecules?
Elements that exist only as molecules.
Which periodic group are most often diatomic molecules?
Halogens
What happens when compound is formed of only nonmetals or nonmetals and metalloids?
Molecular compounds are created.
If metals are present in a compound, will it have a molecular structure?
No, not typically.
Ammonia
NH3
Naming order for compounds of two elements?
Elements are named first if they are further to the left. If they are in the same group, the element from further down is named first.
1
mono-
2
di-
3
tri-
4
tetra-
5
penta-
6
hexa-
7
hepta
8
octa
9
nona
10
deca
Valence Electrons?
Shared electrons in the outer most shell of an electron.
What is the correlation between main group elements and valence electrons?
Groups 1-8. Have 1-8 valence electrons from left to right.
How many valence electrons in He?
2 (despite the fact that it is in group 8)
What is covalent bonding?
The creation of bonds through the sharing of electrons.
What is the octet rule?
Covalent bonds are created the result in 8 electrons around each atom.
What molecule is stable with two electrons?
Hydrogen
The “-ide” form of fluorine
fluoride
Which group is best known for including diatomic molecules?
Halogens
What element goes at the center when to triatomic and polyatomic molecules?
Generally the first atom in the formula is at the center. H2O is an exception.
Ionic Bonds
Atoms transfer electrons to each other. It generate two oppositely charged ions.
What happens to metal when it becomes an ion?
Metal loses electrons to become a positively charged
Naming binary molecular compound?
Choose the element on the left first. If the elements from the same column choose the element further down first. Add the appropriate prefixes each elemetn to indicate the number of the element’s atoms. For the first atom named, do not add the numeric prefix if it would be mono- Apply the suffix -ide to the second element.
What is the octet rule?
All elements want to complete their outer shell and be more like the noble gasses, which have 8 electrons in their outer shell.
Do metals gain or loose electrons when they form ionic compounds?
Lose. Their charge becomes positive and they form cations.
Do non-metal gain or loose electrons when they form?
Gain. They become positively charged and form anions.
What are Ione pairs?
Electrons that are only on one atom.
What are bonding pairs?
Electrons that are shared between two atoms.
Why do halogens so often exist in diatomic molecules?
Since they have 14 electrons in their outer shell, they get to an octet when they are together.
How does hydrogen exist in nature?
As a diatomic molecule. Because when it only has one electron, so when it bonds with another Hydrogen, each are able to share two.
Can Hydrogen be a central atom?
No, because hydrogen requires a only a duet, it will never be a central atom because central atoms must form more than one bond.
For polyatomic ions, must I add or subtract dots to reflect the ions charge?
Yes.
What is Boron (B) exception to the octet rule?
It can form bonds with three electrons. Meaning Boron is complete when it shares 3 electrons. It has has a tendency to form bonds with 6 electrons.
Which compounds can have more than 8 electrons around them?
P, S, Cl, Br, I can have octets with 10, 12, or 14 valence electrons.
Describe the NO exception to the octet rule?
N has only seven valence electrons in this circumstance.
Name two example where the central atom has more than 8 electrons around it.
SF6 and PCl5
What are resonance structures?
Molecules that contain more than one possible arrangement of dots.
Do the resonance structure for NO2-
Blank
How many valence electrons does a sodium ion contain?
- If it is an ion that means it has either gained or lost an electron. Since it is a metal, when it becomes an ion, it becomes a cation. Since it starts with only one electron in it outer shell, it only has one to lose and the charge goes to 0.
What are Ione pairs?
Valence electrons that are not shared.
Draw the resonance structure for NO3-
Check all three structures online.
How are ionic compounds formed?
When metal lose electrons combine with non-metals which gain electrons, electrons transfer from the metal to the non-metal.
What is the charge of transition metal ions?
Various.
What ionic charges are known?
Group 1: 1+ Group 2: 2+ Group 3: 3+ Group 5: 3- Group 6: 2- Group 7: 1-
What happens when atoms gain or lose electrons?
They have the same number of electrons as their nearer noble gas.
How many valence electrons in each neutral atom group 1-8?
1-8
How many valence electrons in each ion in groups 1-8
Groups 1-4: 0 Groups 5-8: 8
How many valence electrons in non-metal ions?
8
How many valence electrons in metal ions?
0
What is the sum of the charges for ionic compounds?
0
How do you decide the chemical formula for ionic compounds?
Whatever will give the lowest whole number ratio that will balance the charges.
What are the potential oxidation states of hydrogen?
+1 when it combines with a non-metal -1 when it combines with a metal.
What is the difference between typical charge and typical oxidation state?
For our purposes now, nothing.
What is the typical oxidation state for aluminum?
+3
What is the typical oxidation state for group 6a non-metals?
-2
What is the typical oxidation state for 5a non-metals?
-3
What is the typical oxidation state for halogens?
-1
Should metals or non-metals be written first in ionic compounds?
Metals
Acetate
C2H3O2-
Carbonate
CO32-
Hydrogen Carbonate (or bicarbonate)
HCO3-
Hydroxide
OH-
Nitrate
NO3-
Nitrite
NO2-
Chromate
CrO42-
Dichromate
Cr2O72-
Phosphate
PO43-
Hydrogen Phosphate
HPO42-
Ammonium
NH4+
Hypochlorite
ClO-
Chlorite
ClO2-
Chlorate
ClO3-
Perchlorate
ClO4-
Permanganate
MnO4-
Sulfate
SO42-
Sulfite
SO32-
Hydrogen sulfite (or bisulfite)
HSO3-
Hydrogen sulfate
HSO4-
Peroxide
O22-
Cyanide
CN-
C2H3O2-
Acetate
CO32-
Carbonate
HCO3-
Hydrogen Carbonate (or bicarbonate)
OH-
Hydroxide
NO3-
Nitrate
NO2-
Nitrite
CrO42-
Chromate
Cr2O72-
Dichromate
PO43-
Phosphate
HPO42-
Hydrogen Phosphate
NH4+
Ammonium
ClO-
Hypochlorite
ClO2-
Chlorite
ClO3-
Chlorate
ClO4-
Perchlorate
MnO4-
Permanganate
SO42-
Sulfate
SO32-
Sulfite
HSO3-
Hydrogen sulfite (or bisulfite)
HSO4-
Hydrogen sulfate
O22-
Peroxide
CN-
Cyanide
What is the relationship between -ate and -ite?
In compound with these endings, the -ate always has one more oxygen than the -ite
When naming ionic compounds, what does hypo mean?
One less than.
When naming ionic compounds, what does per-mean?
One more than.
What are Type I ionic compounds?
Compounds formed from metal with an invarinat charge.
What are Type II ionic compounds?
A compound that contains metals with variable charges.
Where are metal that form Type II ionic compound usually found?
In the transition metals.
What is the charge of Ag?
+1
What is the charge of Zn?
+2
How are ionic compound named?
The metal is named first. The non-metal ending is exchanged for -ide.
How do I name ionic compound named form the transition metals.
Since charge is not
What is the oxidation state of Zinc?
+2
Why are there no charges given for names of ionic compounds of Alkali and alkaline earth metals?
Because their charges don’t vary, there is only one compound they can form.
How do you name Type I (invariant charge) ionic compounds?
Name of less negative element and then name of mor negative element with the suffix -ide added.
How does one name Type II ionic compound (variable charges)?
1.) Less negative element. 2.) Roman numeral indicating oxidation state 3.) -ide suffix
What is the oxidation state of atoms in their elemental state?
0
What is the name for ZnCl2
Althought zinc is a transition metal, it doesn’t have a variable oxidation state, so its name is simply Zinc Chloride.
What is aluminum’s charge?
Almost alway +3
