Chemistry Topic 3 Flashcards
Periodic Table
How do you find the effective nuclear charge?
Atomic number - number of nonvalence electrons
What two factors cause the outer electrons to not experience the full nuclear charge?
Repulsion and shielding
What is the nuclear charge?
The atomic number
What is the trend for effective nuclear charge across a period?
The effective nuclear charge increases because the number of shielding electrons remains the same, but the nuclear charge increases
What is the trend for effective nuclear charge down a group?
The effective nuclear charge remains the same because the nuclear charge and number of shielding electrons both increase by 8
How do we find the atomic radius?
Atomic radius is half the distance between the nuclei of neighboring atoms
*Must be solved this way because electrons are in orbitals and their exact location is unknown
Cations are (smaller/larger) than their atoms
Smaller
Anions are (smaller/larger) than their atoms
Larger
Electron affinity
A measure in the change in energy when 1 mole of electrons is added to 1 mole of gaseous atoms to form gaseous ions
When the first electron is added in electron affinity, is the reaction endothermic or exothermic?
Exothermic
When does electron affinity become an endothermic process?
When a second electron is added because the anion and second electron repel
Electronegativity
A measure of an element’s attraction for an electron in a covalent bond/a bonding pair of electrons
Down group 1, do melting points increase or decrease? Explain why.
Melting points decrease because the atomic radius increases which makes it harder for the metallic bonds to reach the electrons in other atoms, so the IMFs are weaker, and it takes less energy to melt
Down group 17, do melting points increase or decrease? Explain why.
Melting points increase because atomic radius increases, so the strength of the temporary dipoles in London dispersion forces increases, so the IMFs are stronger, and it takes more energy to melt
Group 17s are diatomic, when size of molecules increases, LDFs increase
Metalloids and macromolecules (network solids) have ____ melting points
Very high
Metals have ____ melting points
High
Nonmetals have ____ melting points
Low
Noble gases have ____ melting points
Very low
Does reactivity for metals increase as you go up or down the groups?
Down
Does reactivity for nonmetals increase as you go up or down the groups?
Up
Group 1 metals react with halogens to form what?
Ionic salts
What do group 1 metals form when they react with water?
A base and hydrogen gas
When a group 1 reacts with water is the reaction endothermic or exothermic?
Exothermic
Metal oxides are (acidic/basic)
Basic
Nonmetal oxides are (acidic/basic)
Acidic
What products do an acid + base produce?
Water + a salt
What do metal oxides + water produce?
A base
What do nonmetal oxides + water produce?
An acid
P4O10 + _H20 -> _____
6H20; 4H3PO4
P4O6 + _H20 -> _____
6H20; 4H3PO3
SO3 + H20 -> _____
H2SO4
SO2 + H2O -> ____
H2SO3
Cl2O7 + H2O -> ____
2HClO4
Cl2O + H2O -> ____
2HClO
What is an amphoteric oxide and what is an example of one?
An oxide that can act as both an acid and a base. Al2O3
What is a Lewis acid?
Something that accepts an electron
What is a Lewis base?
Something that donates an electron
What color and phase is fluorine?
Yellow gas
What color and phase is chlorine?
Yellowish/green gas
What color and phase is bromine?
Dark red liquid
What color and phase is iodine?
Purple solid
In order for a displacement reaction to happen, the free element must be ____ than the element in the compound that its replacing
More reactive (higher up on the table for nonmetals)
For displacement reactions with halogens, the color that is seen is always determined by what?
The free element that isn’t in the compound
What happens if the free element is less reactive than the element it is replacing in a displacement reaction?
No reaction or color change occurs
What fact about the d sublevel do all transition elements have as atoms or ions?
They all have incomplete d sublevels
Transition elements form _____ with ligands
Complex ions
What two elements in the d-block aren’t transition elements in their atom and ion form?
Zinc/Zinc+2 and Copper/Copper+1
What element in the d-block is not a transition element ONLY in its ion
Scandium (+3 ion)
True or false: transition elements have catalyst and magnetic properties
True!
Which two transition elements have high oxidation states, which makes them good oxidation agents down to +3 and +2?
Chromium and manganese
List two examples of homogeneous catalysts
Fe+3 Heme in blood to transport oxygen, and Co+3 in vitamin B12
What are the two possible heterogeneous catalysts in catalytic converters in cars, and what do they do?
Palladium and platinum (solids), and they reduce NO and CO production
What is the name of the process that produces ammonia with the help of a catalyst, and what is that catalyst?
The Haber process, and solid iron is the heterogeneous catalyst
What catalyst is used for a contact process production of sulfuric acid, and what is the equation of the reaction?
Vanadium (V) oxide (V2O5)
Equation: 2SO2(g) + O2(g) -> 2SO3(g)
What is a hydrogenation reaction (equation and catalyst)?
C2H4(g) + H2(g) -> C2H6(g)
Where Nickel is the heterogeneous catalyst that turns an alkene into an alkane (makes an unsaterated hydrocarbon saturated)
What is the decomposition of hydrogen peroxide (equation and catalyst)?
H2O2(aq) -> 2H2O(l) + O2(g)
Manganese (IV) Oxide (MnO2) is the catalyst
Which group is more reactive, group 1 or group 2?
Group 1
List the properties of paramagnetic things
- Unpaired electrons
- Pulled into a magnetic field
- Do NOT retain magnetic properties after the field is removed
- More unpaired electrons = more attraction
List the properties of diamagnetic things
- Paired electrons
- Weakly repelled by magnetic field
- Do NOT retain magnetic properties after the field is removed
List the properties of ferromagnetic things
- Unpaired electrons that align parallel to each other in domains
- Retain magnetic properties when the magnetic field is removed
What are Complex ions?
Transition metal ions, due to their small size, act as Lewis acids (are electron deficient) and attract species that are electron rich called ligands
Are ligands Lewis acids or bases?
Bases
What are Ligands?
Species with lone pair(s) of electrons that form coordinate covalent bonds with a central metal ion
The _____ the oxidation states, the more likely to have covalent properties
higher
List the spectrochemical series in order from weakest to strongest
I- < Cl- < F- < OH- < H2O < SCN- < NH3 < NO- < CN- = CO-
What is a coordinate covalent bonds?
A bond where one element donates both electrons, and the other does nothing
What is a monodentant ligand?
A ligand that forms one coordinate covalent bonds using one lone pair of electrons
If the ligand is neutral, how do we find the charge of the central metal ion?
Its just whatever the charge of the complex ion is
What is the charge of ammonia
Nothing!
Coordination number
The number of coordinate covalent bonds formed from the ligand to the central metal ion
Polydentate Ligands
Contain MORE THAN 1 pair of lone electrons and can form 2 or more coordinate covalent bonds to the metal ion
Bidentant Ligands
Can form 2 coordinate covalent bonds
Hexadentate Ligand
Has 6 atoms with lone pairs of electrons
Chelates
2 or more separate coordinate covalent bonds between ligand and central atom
What is the color of the transition metal related to?
The presence of partially filled d orbitals
If a transition metal appears yellow, what color light is it absorbing?
Purple! - Always the complementary color on the color wheel
Which three ions are always colorless and why?
Sc 3+
Zn 2+
Cu 1+
Because they do not have any partially filled d orbitals
In a free ion, the d orbitals are all of _____ energy, so they are called _____
Equal; degenerate
Where are the five d orbitals located?
3 are between the axis, and 2 are along the axis
Why do the 2 d orbitals that are along the axis split apart from the other 3 when a ligand comes in?
The lone electron(s) in the ligand repel the orbitals
The amount of _____ determines the color reflected in a complex ion
The amount of energy in the splitting
List the four things that cause the splitting energy to change
Identity of central metal ion, oxidation state of metal ion, geometry of complex ion, and identity of ligand
Do larger central metals provide greater or less splitting of the d orbitals?
Greater!
Great amounts of splitting in the d orbitals = (high/low) energy = (high/low) frequency = (high/low) wavelength
High energy, high frequency, low wavelength
In the same metal, as the oxidation state increases, does the splitting of the d orbitals increase or decrease?
Increase!
How can you tell if the geometry of the complex ion is what’s changing the splitting in the d orbitals?
If the only difference is the number of Ligands
How many ligands are attached in an octahedral complex ion? tetrahedral? linear?
6, 4, 2
If there are more ligands attached in a complex ion, is there more or less splitting?
More Ligands = more splitting
Stronger Ligand = (more/less) splitting
More!
When some of the water ligands in a [Cu(H20)6]2+ ion are replaced with ammonia, does the splitting increase or decrease? Also, what color will the new ion be?
The splitting increases, and the new ion will be dark blue/violet
If you were to arrange ions in order of largest radius to smallest, and they all have the same charge, which one would have the largest ionic radius?
Whichever one has the largest atomic radius
Are elements Lu and Lr part of the d or f block?
d block
Are elements La and Ac part of the d or f block?
f block
Explain why there is a large increase in ionic radius from Si 4+ to P 3-
P 3- has another energy level
Explain why sulfur has a higher melting point than phosphorus
Phosphorus has a greater atomic radius than sulfur, so sulfur atoms are more tightly held together, and therefore it takes more energy to break them apart
For individual atoms, small radius = strong IMFs
Does a bigger molecule mean stronger or weaker London dispersion forces?
Stronger!
What happens when a group 1 metal is added to water?
H2 is created, the temperature of the water increases, and a clear, colorless solution (a base) is formed (also it explodes)
What does the spectrochemical series list?
Ligands in order of their ability to split the d orbitals of transition metals
What are the products of a reaction between chlorine and water?
HCl and HOCl
Don’t really have to know this, just know that it should produce acids
What is the maximum amount of orbitals in the n=2 energy level?
4 (1 from 2s, 3 from 2p)
Are metalloids acidic or basic?
Acidic!
What is an essential feature of a ligand?
The presence of a non-bonding pair of electrons
If all the ions have the same number of electrons (but they’re different elements), how do you determine which one is the smallest and largest?
Whichever one has the most amount of protons is the smallest because it can pull the electrons in closer, and whichever has the least amount is the biggest
What are the three ferromagnetic elements?
Iron, Cobalt, Nickel
Can bromine oxidize iodine?
Yes! Br2 + KI -> I2 + KBr, so Iodine goes from being a -1 to a 0, so it is losing an electron
Where do transition metals lose their first electron from?
The outermost s orbital
When the valence electrons are closer to the nucleus, they are ____ likely to react
Less!
