Chem 171 Midterm 2 – Flashcards

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question
Write a balanced chemical equation for the reaction
between sodium hydride and water
answer
NaH + H20 -> NaOH + H2
(hydrides hydrolyze to give hydrogen and hydroxides)
question
Write a balanced chemical equation for the formation of synthesis gas
answer
CH4 + H20 -> CO + 3H2
(synthesis gas is a mixture of CO and H2)
question
Write a balanced chemical equation for the hydrogenation of ethene, H2C=CH2, and give the oxidation number of the carbon atoms in the reactant and product;
answer
CH2=CH2 + H2 -Ni-> CH3-CH3
(double bonds hydrogenate to give single bonds)
question
Write a balanced chemical equation for the reaction of magnesium with hydrochloric acid
answer
Mg + 2HCl -> MgCl2 + H2
(metals react with acid to give hydrogen)
question
Identify the products and write a balanced equation for
the reaction of hydrogen with nitrogen
answer
N2 + 3H2 -> 2NH3
(oxidize N2)
question
Identify the products and write a balanced equation for
the reaction of hydrogen with fluorine
answer
H2 + F2 -> 2HF
(reduce F2)
question
Identify the products and write a balanced equation for
the reaction of hydrogen with cesium
answer
2Cs + H2 -> 2CsH
(oxidize Cs to Cs+)
question
Identify the products and write a balanced equation for
the reaction of hydrogen with copper(II) ions
answer
H2 + Cu2+ > 2Cu + 2H+
(reduce Cu2+ to metal)
question
Write the chemical equation for the reaction between cesium and oxygen (cesium reacts with oxygen in the same way as potassium)
answer
Cs + O2 > CsO2
(gives cesium superoxide)
question
Write the chemical equation for the reaction between
sodium oxide and water
answer
Na2O + H2O > 2NaOH
(gives sodium hydroxide)
question
Write the chemical equation for the reaction between lithium and hydrochloric acid
answer
2Li + 2HCl > 2LiCl + H2
(alkali metal reacts with water to give hydrogen)
question
Write the chemical equation for the reaction between cesium and iodine
answer
2Cs + I2 > 2CsI
(similar to sodium plus chlorine)
question
Predict the products of each of the following reactions
and then balance each equation:
(a) Mg(s) Br2(l) ->
answer
Mg + Br2 > MgBr2
(alkaline earth reacts with halogen)
question
Predict the products of each of the following reactions
and then balance each equation:
(b) BaO(s) Al(s) ->
answer
3BaO + 2Al > Al2O3 + 3Ba
(similar to thermite)
question
Predict the products of each of the following reactions
and then balance each equation:
(c) CaO(s) SiO2(s) ->
answer
CaO + SiO2 > CaSiO3
(formation of silicates)
question
Al2O3 + OH- ->
answer
Al2O3 + OH- + 3H2O -> 2Al(OH)4-
question
Al2O3(s) H3O(aq) H2O(l) ->
answer
Al2O3 + 6H3O+ + 3H2O > 2Al(H2O)6
3+
question
B(s) NH3(g) S ->
answer
2B + 2NH3 > 2BN + 3H2
question
The diatomic molecule BF can be obtained by the
reaction between BF3 and B at a high temperature and low
pressure. (a) Determine the electron configuration of the
molecule in terms of the occupied molecular orbitals and
calculate the bond order.
answer
Assuming that BF will display the same molecular orbital energy level order as 2
N , the
ground-state electron configuration will be

(?1s )2 (?1s
* )2 (?2s )2 (?2s
* )2 (?2 p )4 (?2 p )2 ;
BO =

1 2 (10 ? 4) = 3
question
The diatomic molecule BF can be obtained by the
reaction between BF3 and B at a high temperature and low
pressure.(b) CO is isoelectronic with BF. How
do the molecular orbitals in the two molecules differ?
answer
(b) The molecular orbitals in CO and BF differ in shape and energy since the atoms involved in bonding have different atomic orbital energies and sizes. The orbitals of BF will
more closely resemble those of HF while those of CO will more closely resemble those of 2N
(see Chapter 4).
question
Identify the oxidation number of tin in the following compounds and ions: (a) Sn3(OH)42+
answer
(a) +2
question
Identify the oxidation number of tin in the following compounds and ions:(b) K2SnO3
answer
(b) +4
question
Identify the oxidation number of tin in the following compounds and ions:(c) K2Sn3O7
answer
(c) +4
question
Balance the following skeletal equations and classify
them as acid–base or redox:
(a) CH4(g) S8(s) S CS2(l) H2S(g)
answer
(a) 2CH4(g) + S8(s) > 2CS2(l) + 4H2S(g) (redox)
question
(b) Sn(s) KOH(aq) H2O(l) S K2Sn(OH)6(aq) H2(g)
answer
(b) Sn(s) + 2KOH(aq) + 4H2O(l) > K2Sn(OH)6(aq) + 2H2(g) (redox)
question
Nitrous acid reacts with hydrazine in acidic solution
to form hydrazoic acid, HN3. Write the chemical equation and
determine the mass of hydrazoic acid that can be produced
from 15.0 g of hydrazine.
answer
HNO2 + H2NNH2 > 2H2O + HN3
15.0 g (1/32.05 g/mol) (43.04 g/mol HN3) = 20.1 g HN3
question
Suggest a method for preparing
sodium azide, NaN3.
answer
N2O + 2NaNH2 >NaN3 + NaOH + NH3
my solution: NaOH + HN3 > NaN3 + H2O.
question
Is the production of hydrazoic acid an
oxidation or a reduction of hydrazine?
answer
The oxidation number of nitrogen in hydrazine is -2, while in hydrazoic acid it is nominally
-1/3 so this is an oxidation process as far as hydrazine is concerned.
question
The common acid anhydrides of phosphorus are P4O6
and P4O10. Write the formulas of their corresponding acids
and chemical equations for the formation of the acids by the
reaction of the anhydrides with water.
answer
P4O6 + 6H2O > 4H3PO3
P4O10 + 6H2O > 4H3PO4
question
Draw the Lewis structure for oleum, (HO)SO2-O-SO2(OH), prepared by treating sulfuric acid with SO3.
answer
The formal charges are 0 on all S and O atoms
question
Determine the
formal charges on the sulfur and oxygen atoms (HO)SO2-O-SO2(OH)
answer
The formal charges are 0 on all S and O atoms
question
What is
the oxidation number for sulfur in this compound? (HO)SO2-O-SO2(OH)
answer
+6
question
Write the Lewis structure for BrF3. What is the
hybridization of the bromine atom in the molecule?
answer
AX3E2, T-shaped, sp3d
question
Determine the oxidation number of the noble-gas
element in (a) XeO3; (b) XeO6
4-; (c) XeF2; (d) HXeO4-
answer
(a) XeO3 O = -2 Xe = 6
(b) XeO64- Xe=8
(c) XeF2 Xe=2
(d) HXeO4- Xe=6
question
Explain why the density of vanadium (6.11 gcm3) is
significantly less than that of chromium (7.19 gcm3). Both
vanadium and chromium crystallize in a body-centered cubic
lattice.
answer
Cr has a smaller radius than V (129 pm vs 135 pm) and a larger atomic mass (52.0 vs 50.94
g/mol)
This provides the estimate (135/129)3 (52.00/50.94) = 1.16. The observed is 1.18
question
Which of the elements scandium, molybdenum, and
copper is most likely to form a chloride with the formula MCl4?
Explain your answer.
answer
In MCl4, M has an oxidation number of +4. Referring to Figure 16.6, we see that Mo is the
only element with a +4 oxidation state.
question
Name each of the following complex ions and determine
the oxidation number of the metal: (a) [CrCl3(NH3)2(OH2)]+
answer
diammineaquatrichloridochromium(IV) ion
Let x = oxidation number to be determined
x(Cr) + [3 ? (?1)] = +1
x(Cr) = +1 ? (?3) = +4
question
Name each of the following complex ions and determine
the oxidation number of the metal:(b) [Rh(en)3)]3+
answer
tris(ethylenediamine)rhodium(III) ion
x(Rh) + 3 ? (0) = +3
x(Rh) = +3
question
Name each of the following complex ions and determine
the oxidation number of the metal:[Fe(ox)(Br)4]3-
answer
tetrabromido(oxalato)ferrate(III) ion
x(Fe) + [1 ? (?2)] + [4 ? (?1)] = ?3
x(Fe) = ? 3 ? (?6) = + 3
question
Name each of the following complex ions and determine
the oxidation number of the metal: [Ni(OH)(OH2)5]2+
answer
pentaaquahydroxonickel(III) ion
x(Ni) + [5 ? (0)] ? [1 ? (?1)] = + 3
x(Ni) = + 3
question
Use the information in Table 17.4 to write the formula
for each of the following coordination compounds:(a) triamminediaquahydroxidochromium(II) chloride
answer
(a) [Cr(OH)(NH3)3(H2O)2]Cl
question
Use the information in Table 17.4 to write the formula
for each of the following coordination compounds:(b) potassium tetracyanido-Cplatinate(II)
answer
(b) K2[PtCN4]
question
Use the information in Table 17.4 to write the formula
for each of the following coordination compounds:(c) tetraaquadichloridonickel(IV) iodide
answer
(c) [NiCl2(H2O)4]I2
question
Use the information in Table 17.4 to write the formula
for each of the following coordination compounds:(d) lithium tris(oxalato)cobaltate(III)
answer
(d) Li3[Co(C2O4)3]
question
Use the information in Table 17.4 to write the formula
for each of the following coordination compounds:(e) sodium bromidohydroxidobis(oxalato)rhodate(III) octahydrate
answer
(e) Na3[RhBr(OH)(C2O4)2] 8 H2O
question
With the help of Table 17.4, determine the coordination
number of the metal ion in each of the following complexes:(a) [PtBr2(NH3)2];
answer
(a) 4
question
With the help of Table 17.4, determine the coordination
number of the metal ion in each of the following complexes:(b) [Ni(en)2I2]+
answer
(b) 6
question
With the help of Table 17.4, determine the coordination
number of the metal ion in each of the following complexes:(c) [Co(ox)3]3-
answer
(c) 6
question
With the help of Table 17.4, determine the coordination
number of the metal ion in each of the following complexes:(d) [Mn(CO)5]-
answer
(d) 5
question
Draw an orbital energy-level diagram (like those in
Figs. 17.29 and 17.31) showing the confi guration of
d-electrons on the metal ion in each of the following complexes:
(a) [Zn(OH2)6]2; Predict the number of unpaired electrons for
each complex.
answer
[image]
question
Draw an orbital energy-level diagram (like those in
Figs. 17.29 and 17.31) showing the confi guration of
d-electrons on the metal ion in each of the following complexes:
(b) [CoCl4]2 (tetrahedral). Predict the number of unpaired electrons for
each complex.
answer
[image]
question
Draw an orbital energy-level diagram (like those in
Figs. 17.29 and 17.31) showing the confi guration of
d-electrons on the metal ion in each of the following complexes: (c) [Co(CN)6]3; Predict the number of unpaired electrons for each complex.
answer
[image]
question
Draw an orbital energy-level diagram (like those in
Figs. 17.29 and 17.31) showing the confi guration of
d-electrons on the metal ion in each of the following complexes:
(d) [CoF6]3. Predict the number of unpaired electrons for
each complex.
answer
[image]
question
what is the most abundant element in the universe?
answer
hydrogen; it is a transparent gas under normal conditions, it can form both a cation and an anion
question
what is made industrially as a by-product of petroleum refining via two reactions?
answer
hydrogen
question
what are the two reactions for making of hydrogen industrially as a by product of petroleum refining?
answer
1)steam reforming (using a nickel catalyst)
CH4 + H2O --> CO + 3H2
2)water gas-shift reaction (iron/copper catalyst)
CO + H2O --> CO2 + H2
question
what are other sources of hydrogen production?
answer
1) dissolve metal in acid
2)electrolysis
3)use sunlight to split water: 2H2O -->2H2 + O2 (endothermic by 400 kJ/mol) TiO2 catalysis
4) biological production (photosynthesis by algae in low sulfur environments)
question
Groups 1-2 form what with hydrogen?
answer
salt-like hydrides
question
Groups 3-12 form what with hydrogen?
answer
metallic hydrides, which are black, powdery, electrically conducting solids; possible hydrogen storage via M + H2 -->MH2
question
Groups 13-17 form what with hydrogen?
answer
molecular hydrides, many of which are gases
question
what is hydrogen bonding?
answer
compounds with a bond between hydrogen and nitrogen, oxygen, or fluorine-elements with small, highly electronegative atoms-participate in this very strong intermolecular force; it is about 5% as strong as covalent bond between same types of atoms, but ten times stronger than other intermolecular interactions
question
what do hydrogen bonds come from?
answer
partially from coulomb attraction between partial charges and partially from weak bonding interactions
question
why are hydrogen bonds important?
answer
1) ice floats because of hydrogen bonds
2) hydrogen bonds hold DNA together
3) hydrogen bonds determine important features of protein structure
question
how are pure alkalis usually made?
electrolysis
answer
(Na+) + (Cl-) --> Na + (1/2) Cl2 (g) (Downs Process)
question
what is NaHCO3?
answer
baking soda (bicarbonate of soda)- reacts with weak acid to form CO2 in bread
question
what is NaCO3?
answer
washing soda (provides carbonate in solution that precipitates Mg2+)
question
what is NaNO3 and KNO3?
answer
oxidizing agent in black gunpowder, also used in matches
2KNO3 + 4C --> K2CO3(s) + 3CO(g) + N2(g) [produces lots of gas so explosion occurs]
question
how are true alkaline earth metals obtained?
answer
by electrolysis or by reduction with aluminum in a version of the thermite process:
3BaO + 2Al --> Al2O3 + 3Ba
MgCl2 -->(Mg2+) +2(Cl-)
question
properties of beryllium
answer
-metallic and nonmetallic properties
-does not react with water
-often quite poisonous
question
key difference between alkalis and alkali earth salts
answer
not water soluble-most notable: CaCO3
question
primary uses of alkaline earths
answer
1)Mg(OH)2 (milk of magnesia)
2) MgSO4-epsom salts-inhibit absorption of water from the intestine, results in defacation
3)quicklime (CaO), which reacts with water to give slaked lime (Ca(OH)2). This is an inexpensive base that is used for agriculture
4)Concrete (gravel plus Portland cement). Portland cement is pellets of CaO mixed with gypsum, CaSO4-2H2O
question
boron is mined as?
answer
borax Na2B4O7 xH2O (x=10)
question
pure B can be used for...
answer
production of stiff, light fibers that are used in plastics
question
boron compounds include...
answer
1) BF3BCl3 (boron triahalide) is an industrial catalyst, acts as a Lewis acid
2) NaBH4 (sodium borohydride) is an important reducing agent
question
aluminum comes from?
answer
bauxite- a hydrated, impure oxide (Al2O3 xH2O)
found in earths crust
question
aluminum metal is obtained by?
answer
the hall process-to give pure Al. Key to the Hall process is use of an alumina (Al2O3)/cryolite (Na3AlF6) mixture which gives a melt at 950 celsius rather than pure alumina (2050 Celsius) for the elctrolysis
question
Aluminum compounds are:
answer
1)Al2O3 (alumina) has several crystal forms:
alpha-Al2O3 is corundum, which shows up in sandpaper
gamma-Al2O3 is used in chromatography for adsorption
2) AlCl3 6H2O is used as a deodorant and antiperspirant (kills bacteria)
question
what are the forms of pure carbon?
answer
-diamond
-graphite(most stable at room temp.)
-fullerenes (C60)
-carbon nanotubes
question
other forms of carbon (other than pure carbon)
answer
1) soot, carbon black are small crystals of graphite-used in ink
2) activated charcoal is highly porous graphitic carbon
question
other important inorganic carbon compounds:
answer
1)CCl4, CHCl3, CH2Cl2 (carbon tet, chloroform, methylene chloride) important solvents
2)CF4 (refrigerant), CBr4 (fire extinguishing material)
3)SiC (silicon carbide or carborundum) is used as an abrasive
question
what is zone refining used for?
answer
possible to produce ultra pure Si that are needed for semiconductor manufacturing. In zone refining an electric heater is swept across a cylindrical sample, locally melting the silicon. The impurities collect in the molten state, allowing for their removal. This makes possible the production of Si that is pure to 1 part in 10^9, which is a key requirement of semiconductor of electronics. Zone refining was discovered at Bell Labs in the late 1940s.
question
Forms of silicon:
answer
1)Pure silicon has the diamond structure
2) amorphous silicon (used in photovoltaics)
(no graphitic form of silicon, or fullerenes or tubes as silicon doesn't form double bonds with itself)
question
Silicon applications:
answer
1)Field effect transitors(discovered at Bells labs by Bardeen, Brattain, Shockley)
2)Solar cells (discovered at Bell labs by Pearson, Chapin, Fuller)
question
Silicon compounds include:
answer
1)Silica (SiO2) used in making glass, ceramics
2) Silica gel (hydrated SiO2) used from chromatography media, as a drying agent
3)Aluminosilicates (replace Si4+ by some amount of Al3+ in silica). This has many forms, such as mica, feldspar, cements (after roasting with lime)
4)Silanes, silicone?? (-O-Si-O-Si-) used as lubricants and for waterproofing
question
germanium
answer
a semiconductor similar to Si, but much less important (although the first transistors were Ge)
question
tin
answer
produced from SnO2 by reaction with C. used in tin cans
question
lead
answer
produced from PbS (galena) by oxidation, then reaction with C. Used on pipes, glazes, paint in the past, but now phased out because of toxicity. Significant uses now are in X-rays and lead-acid batteries
question
how is pure nitrogen made?
answer
by liquifying air, followed by fractional distillation
question
what is the industrial process for making ammonia?
answer
the haber process: it involves the reaction N2+ 3H2 --> 3NH3 (performed at high temperature and pressure and with an iron catalyst)
*this produces 1.6 x 10^10 kg of ammonia each year, and the ammonia that is produced is used in fertilizer, polymers, explosives and many other applications
question
how is nitrogen fixation accomplished in nature?
answer
bacteria
question
important nitrogen compounds:
answer
1)NH3
2)NH4NO3 explosive and fertilizer
3) NaN3 (sodium azide) this decomposes into Na and N2 when shocked. used in air bags
4) NO2 (nitrogen dioxide), NO (nitric oxide), N2O (nitrous oxide). These oxides of nitrogen show up in many places in modern life. NO2 is a component of song, NO is used in biology for signaling, N2O is an anesthetic
6) HNO3 (nitric acid), HNO2 (nitrous acid), HNO (hyponitrous acid) HNO3 is a strong acid that is used in making fertilizer. HNO2 is used in making nitrites (preservative)
question
how is superphosphate made?
answer
from Ca3(PO4)2 by heating with C and sand
question
what is stable form of phosphorous?
answer
P4(white phosphorous). This changes into red phosphorous (chains of linked P4 tetrahedra) when heated in the absence of air
*white phosphorous ignites spontaneously in air; red phosphorous is less reactive, but still can be used in the striking surfaces in matchbooks
question
Phosphorous compounds:
answer
1) PH3 (phosphine) poisonous gas used in organic chemistry
2) PCl3 and PCl5 used in the synthesis of pesticides, oil additives, flame retardants
3) H3PO4 (phosphoric acid) used in soft drinks, detergents
4) Superphosphate (fertilizer) is a mixture of CaSO4 and Ca(H2PO4)2
question
what are metalloids that are produced in pure from their sulfide ores?
answer
arsenic and antimony
question
most important use of As?
answer
in GaAs lasers for CD players. similarly, InSb is another laser system. GaAs is also used in electronics applications as an alternative to Si
question
how is oxygen produced?
answer
by fractional distillation of liquid air. primarily used in steel manufacturing
question
how is ozone formed?
answer
by photodissociation (O2-->O + O followed by O + O2 --> O3)
question
what is pure sulfur?
answer
S8, it occurs in monoclinic and rhombic forms
question
important sulfur compounds:
answer
1) H2S
2) SO2, SO3
3) H2SO3, H2SO4 (the most heavily produced chemical in USA) used in production of fertilizer, petrochemicals, dyes, detergents
question
fluorine
answer
produced by electrolysis of KF, its a colorless gas (F2) that is highly reactive
-it forms salts that are not as soluble as the chloride salts. this makes F- a much less important component of seawater than Cl-. CaF2 is an essential component of bone, including teeth
question
fluorine compounds:
answer
1)SF6
2)UF6 (used for making nuclear reactor fuel)
3)HF the only weak acid of the hydrogen halides, used for etching of electronic components in the electronics industry
question
how is chlorine manufactured?
answer
from electrolysis of NaCl
question
chlorine compounds:
answer
1)HCl (hydrochloric/muriatic acid)-stomach acid
2)HClO4 perchloric acid (rocket fuel)
HClO3 chloric acid
HClO2 chlorous acid
HClO (hypochlorous acid) active ingredient in chloral
3) many organic compounds (CCl4), chlorinated polymers (PVC)
question
how is bromine produced?
answer
from chlorine 2(Br-) + Cl2 --> Br2 + 2(Cl-)
question
description of fluorine
answer
colorless gas (F2) that is highly reactive
question
description of bromine
answer
Br2 is a red-brown liquid
question
important bromine compounds:
answer
1)HBr
2)Same acids as with Cl
question
how is iodine produced?
answer
from chlorine via 2(I-) + Cl2 --> I2 + 2Cl-
question
description of iodine
answer
I2 is a black solid with purple vapor
question
important compounds of iodine:
answer
1)HI
2) Same acids as with Cl
question
the rare gases are all..?
answer
monatomic gases
question
how are the noble/ rare gases obtained?
answer
all except He and Rn are by fractional distillation
He comes from natural gas wells in Texas
Rn is found naturally in the ground as a result of radioactive processes
question
applications of rare gases:
answer
1)Helium is used for cryogenics, for blimps, for He-Ne lasers
2) Neon, krypton, xenon are used for lighting
3) argon is used for welding in inert atmospheres
4) krypton and xenon are used to make excimer lasers (shortest wavelength commercially available lasers)
question
rare gas compounds?
answer
1) in 1962, Neil Bartlett synthesized XePtF6, which was the first chemical compound involving a rare gas
2) XeF2, XeF4, XeF6, XeO3, XeO4, H2XeO4, XeO6 4-
question
whats a colloid?
answer
particles (1nm to 1 micrometer) suspended in a solvent
question
what brownian motion?
answer
theory that in colloids the particles are in constant motion, which keeps them from settling out. Also, the particles may be charged, so that electrostatic repulsion keeps them from aggregating
question
types of colloids:
answer
1) sol: 1) solid in gas (smoke), aerosol
2) liquid in gas (fog), aerosol
3) solid in liquid (paint)
2)emulsion: liquid in liquid (milk, mayonnaise)
3)gel: solid in liquid that typically has solid texture (jello)
4)foam: gas in liquid
5)solid dispersion: solid in solid (stained glass windows)
6)solid emulsion: liquid in solid (ice cream)
7) solid foam: gas in solid (insulation)
question
all the d-block elements are...
answer
metals, some are good magnets, most are god electrical conductors
question
the radii of the first row of the d-block are mostly the same, but there is a ....
answer
general contraction for the first few (due to the increasing nuclear charge), followed by a slight expansion (due to too many electrons)
*also seen in the second and third rows
question
lanthanide contraction
answer
contraction of the atomic radii going across the lanthanides; arises because the inner shell electrons of the 3rd row transition metals are so close to the nucleus that relativistic effects are important; this makes the electron heavier, which allows them to be located closer to the nucleus. ex: Au and Pt are less reactive, Hg is a liquid
question
possible shapes of complexes depend on..?
answer
how many ligands there are (usually connected to the oxidation number) and to the hybridization of the orbitals on the metal atom
question
elements in the 3rd row of the ... block and ...block have more than 6 ligands
answer
d and f, this leads to the square anti prism structure and dodecahedral structure
question
example of polydentate ligand?
answer
ethylene diammine(en). leads to the possibility of chelate formation, wherein a bidentate ligand forms a ring with the metal atom as one member. the complex EDTA (ethylene diammine tetra acetic acid) is a hexadentate ligand that is often used to "capture" a metal atom to form an octahedral complex
question
when do stereoisomers arise?
answer
when the molecule is superimposable on its mirror image
question
what is an optical isomer?
answer
isomers that are related like an object and its mirror image; identified because they rotate circular polarized light in opposite directions
question
[CrCl(en)2(NH3)]Cl2
answer
amminechloridobis(ethylenediamine)chromium(III) chloride
question
Pentaamminechloridocobalt(III) chloride
answer
[CoCl(NH3)5]Cl2
question
Ligands are....in the formula based on the atom which dominates an electron pair
answer
alphabetical
question
crystal field theory
answer
image that th ligands are simple point charges located at the vertices of the octahedron that defines the symmetry of the complex. This creates an electric field that interacts with the metal atom splitting the d-orbitals. This splitting creates low lying excited states that are responsible for the colors of the complexes.
question
size of splitting in ligands depends on?
answer
the size
question
high spin complexes
answer
associated with weak field ligands
question
low spin complexes
answer
strong field ligands
question
NH3
answer
ammine
question
NO
answer
nitrosyl
question
OH2
answer
aqua
question
CO
answer
carbonyl
question
NH2CH2CH2NH2
answer
ethylenediamine (en)
question
NH2CH2CH2NHCH2CH2NH2
answer
diethylenetriamine (dien)
question
F-
answer
fluorido
question
Cl-
answer
chlorido
question
Br-
answer
Bromido
question
I-
answer
iodido
question
OH-
answer
hydroxido
question
O^2-
answer
oxido
question
CN-
answer
cyanido-kC
question
NCS-
answer
thiocyanto-kN
question
NO2- as ONO-
answer
nitrito-kO
question
NO2- as NO2-
answer
nitro, nitrito-kN
question
CO3^2- as OCO2^2-
answer
carbonoto-kO
question
C2O4^2- as -O2CCO2-
answer
oxalato (ox)
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SO4^2- as OSO3^2-
answer
sulfato
question
for octahedral complex, use a basis set consisting of...
answer
a)five d-orbitals
b)the s and three p orbitals on the metal
c)the six ligand orbitals
question
ligand field theory
answer
nothing other than orbital theory as applied to transition metal complexes, using the valence electrons on the metal and ligands
question
advantages of ligand field theory v. crystal field theory
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in ligand field theory, we can calculate the splittings, and the results are more realistic than with crystal field theory, showing the difference between a strong field and weak ligand field
-allows one to describe more subtle interactions, such as those involving the pi orbitals on the ligands with the metal d-orbitals
question
scandium
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+3 oxidation number, reacts with water, used as alloy to strengthen Al
question
Titanium
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+4 oxidation number, used in aircraft(lightweight). TiO2(rutile) is white paint and semiconductor, photocatalyst (splitting water),
question
BaTiO3
answer
piezoelectric(distorts shape when charged)
question
Vanadium
answer
+5 oxidation number, used as alloy in steel, V2O5 is an oxidant , used as a catalyst in H2SO4 production
question
Chromium
answer
+3 state essential for life(required for insulin to work), available in foods and dietary supplements, +6 state is carcinogenic when airborne
question
Manganese
answer
MnO2 is key component of batteries, KMno4 is an oxidizing agent
question
Iron
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3 grams in the body, mostly as hemoglobin
question
Cobalt
answer
present in vitamin B12, magnets contain Fe, Ni, Co, Al
question
Nickel
answer
nickels are 75% Cu, important in many enzymes, urease, hydrogenase
question
Copper
answer
replaces iron for oxygen transport in some animals, used in bronze, brass, pennies
question
zinc
answer
present in many enzymes, galvanized metal in zinc coated, used in batteries
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Making steel
answer
the reduction of iron ore (Fe2O3 and FeO) to Fe by CO, CO is produced by burning coke
limestone is added to convert impurities into a molten mixture called slag that can be removed
question
pig iron
answer
iron that is made in a blast furnace
question
different zinc "ase"s
answer
carbonic anhydrase (hydrolyze CO2 to make HCO3-)
carboxypeptidase (hydrolyzes peptides in digestion)
alcohol dehydrogenase (converts alcohol to aldehyde)
question
Molybdenum
answer
nitrogenase is a Fe/Mo protein (nitrogen fixation)
this is part of the nitrogenase complex that also includes reductase (an Fe protein)
question
Platinum
answer
cis-[PtCl2(NH3)2] (cis-platin) is used in treating cancer
question
Cobalt
answer
pernicious anemia, compound contains the only C-Co bond in biology
question
steam forming
answer
CH3 + H2O -> CO2 + 3H2
question
Down's Process (for alkalines-1)
answer
2NaCl -> 2Na + Cl2(g)
question
Dow Process
answer
MgCl2 -> Mg + Cl2
question
Hall Process
answer
Al2O3 + Na3AlF6 -> Al+....
question
Haber Process
answer
N2 + 3H2 -> NH3
question
alkali metals with O2
answer
Li, Na, K form oxides M2O
Na with excess O2 forms peroxide M2O2
Rb,Cs,Fr forms superoxide MO2
question
alkali metals with H2O
answer
M + H2O -> MOH + H2
reactivity increases m
question
alkali metals with H2
answer
form hydrides, MH
question
alkaline earths with O2
answer
forms oxide, MO
NOT beryllium
question
alkaline earths with H2O
answer
form metal hydroxides, M(OH)2
not beryllium
question
alkaline earths with H2
answer
form metal hydrides, MH2
question
5 forms of carbon
answer
1)graphite
2)graphene
3)diamond
4)buckyballs
5)nanotube
question
graphite
answer
comes in sheets-sheets of sp2 carbon
question
graphene
answer
single sheet, sp2
question
diamond
answer
tetrahedral, sp3 crystal
question
buckyballs
answer
C60, has double bonds, somewhere between spy and sp3
question
nanotube
answer
rolled graphene, sp2-sp3
question
6 forms of silicon
answer
1)pure silicon
2)amorphous silicon
3)SiO2
4)Alumina silicates
5)silicone
6)carborundum
question
pure silicon
answer
diamond, tetrahedral
question
amorphous silicon
answer
tetrahedral, disordered
question
alumina silicates
answer
mical, feldspar
question
silicone
answer
-Si-O-Si-O-, water repellant
question
carborundum
answer
Si-C, abrasives
question
4 forms of aluminum
answer
1)corrundum
2)alumina
3)bauxide
4)cryolite
question
corrundum
answer
alpha-Al2O3
question
alumina
answer
Al2O3
question
bauxide
answer
mixture of oxides and hydroxides
question
cryolite
answer
Na3AlF6
question
lanthanide contraction
answer
-radius stays the same from period 5 to period 6
-reactivity of 6 is lower than expected
-why Au is so stable
-period 6 more stable and radius is smaller than expected
question
colloids
answer
-aersol
-emulsion/solid emulsion
-gel/sol
-foam/solid foam
question
aerosol
answer
solid/liquid in gas
-ex: smoke or fog
question
emulsion
answer
liquid in liquid
question
solid emulsion
answer
liquid in solid
question
gel/sol
answer
solid in liquid
question
foam/solid foam
answer
gas in liquid/gas in solid
ex: mayo, salad dressing, insulation in houses
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