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2. Nitrogen and Group 5
N is a nonmetal, gas at rm temp; essential for living things
80% of air is N2, but most living things cannot use pure nitrogen-
bacteria fix nitrogen into usable form
N2 is commercially obtained 2 ways, both from air:
1) fractional distillation ( nitrogen boils off first)
2) Air is moved overhot coke ( C) and oxygen isremoved and forms
CO2leaving nitrogen
3. N2 is colorless, odorless, tasteless, slightly soluble in
water
Used to make NH3, ammonia in Haber process (pg 715), and nitric
acid
Ammonia- strong odor, colorless gas, soluble in water, slightly
basic; used in cleaning products, fertilizers, refrigerant
Nitric acid ( can be made from ammonia)-used in etching,
fertilizers, dyes and explosives
Nitrogen and Group 5
4. N video
N video
Bylennox_mcdough
5. P- nonmetal; important in living things (DNA, bones, teeth,
ATP)
Found as phosphate rock
In pure form- 2 types of P- red and white
white is very reactive and stored under water; red is less
reactive-used in matches
Nitrogen and Group 5
6. Arsenic, Bismuth, Antimony
Arsenic, Bi and antimony occur in nature as sulfide minerals
Sb and Bi expand when heated- used in alloys ( printing
presses)
Bi video
Sb video
Ar video
7. Oxygen and Group 6A
O and Snonmetals; Se and Te are metalloids; Po is a radioactive,
metal that occurs in small amounts
8. Oxygen
There are more oxygen atoms in the Earths crust, surface waters and
atmosphere than atoms of any other element.
Molecular oxygen (O 2)makes up 23% by mass of the atmosphere.
Oxygen in compounds make up 46% by mass of the crust and upper
mantle.
In surface waters, oxygen accounts for 86% by mass.
9. Oxygen production
Industrially, oxygen is obtained by liquefying and fractionally
distilling air.
Worldwide production of oxygen is almost 2 x 1011 pounds each year.
This is only 10-5% of the oxygen in the atmosphere.
Molecular oxygen is continuously being
made via photosynthesis by plants that
require carbon dioxide.
Animals breathe in oxygen and breathe out
carbon dioxide.
10. Oxygen use
The major industrial use is in the production of steel.This
accounts for 65-85% of production.
Large quantities of oxygen are also used to produce titanium(IV)
oxide, a white pigment.
Oxygen is also used as an oxidizing agent to power the space
shuttle, for sewage treatment and various industrial
processes.
It also is used in medicine.
11. Physical properties of O2
O2 is a colorless, odorless, tasteless gas.
Solubility.
Only slightly soluble in water.
Less soluble in salt water than fresh water.
Increasing temperature will decrease solubility in water.
It is paramagnetic (weakly magnetic)
12. Ozone
Ozone, O3, is an allotrope of molecular oxygen.
It is prepared by electrical discharge or UV light on molecular
oxygen.
3O2+ 2O2 (g)
Ozone is a diamagnetic blue gas with a characteristic
odor.Concentrations as low as 0.01 ppm can be detected by
odor.
UV or
silent electrical discharge
GOOD UP HIGH
BAD NEARBY
13. Ozone
Ozone is unstable and very reactive,
Catalysts and UV light cause it to decompose.
2O3 (g)3O2 (g)
It is also a more powerful oxidizing agent that molecular oxygen.In
acidic solutions, it is one of the most powerful oxidizing agents
known.
O3 (g) + 2H++ 2e-O2 (g) + H2O (l)Eo = +2.07 V
catalyst or UV
14. Ozone
Atmospheric ozone.
Ozone strongly absorbs UV radiation in the 220-290 nm range.
The ozone layer is stratospheric-level O3.It protects the Earths
surface from the Suns intense UV radiation.
Tropospheric level O3, however, is harmful. It contributes to smog
formation and causes rubber to crack.
GOOD UP HIGHBAD NEARBY
15. Ozone
Ozone as a disinfectant.
O3 is now being used in hospitals, hotels and commercial
laundries.
It is also used to purify drinking water.
Advantage
After reaction, only O2 remains unlike when Cl2 is used.Chlorine
can form chlorocarbons.
Disadvantage
No residual protection.Since it rapidly decomposes, there is no
protection after water treatment.
16. Chemical Properties of O
When substances combine w/oxygen the process is called oxidation,
mostly the products are oxides
Usually this occurs when you heat the elements in the presence of
oxygen
Oxides of metals are usually solids, and can form a basic water
solution
Oxides of nonmetals can be a solid, liquid or gas and tend to form
acidic water solutions
17. Oxygen video
18. Sulfur
S is a yellow, tasteless, odorless, brittle solid
Elemental sulfur has more allotropes than any other elements.
The S-S bond is
the third strongest
single bond between
the same kind of
atoms.
At room temperature,
the most common
form is rhombic,
consisting of
eight member rings.(S8)
19. Sulfur
When sulfur is heated, the packing of the S8 molecules changes
around 96 oC.
Another form of sulfur is monoclinic sulfur.It is stable between
96-119 oC.
When liquid sulfur is heated (160-195 oC), it polymerizes into
chains up to 200 000 S long.
160-195 oC
160-195 oC
20. Sulfur
When liquid sulfur polymerizes, its viscosity increases by a factor
of at least 10 000.
This is because the long chains tend to get tangled up in each
other.
21. Sulfur reactivity
Sulfur is quite a reactive element.
It will react will all elements except nitrogen, tellurium, iodine,
iridium, platinum, gold and the noble gases.
Heating may be necessary to bring about a reaction.
Compounds of all elements except the noble gases with sulfur are
known.
Although it is reactive, sulfur can be found in nature in free as
well as combined form.
22. Sulfur production
Compressed
hot air
Free sulfur occurs in rock over salt domes near the coast of East
Texas and Louisiana and under the Gulf of Mexico.It is mined by the
Frasch process.
Sulfur
Superheated
water
Frasch process
Molten
Sulfur
23. Sulfuric acid and sulfates
Sulfuric acid
It is the cheapest strong acid.
Concentrated sulfuric acid is an oxidizing agent -- but only when
hot.
Cu (s) + 2H2SO4 (conc)CuSO4 (aq) + 2H2O (l) + SO2 (g)
When cold, it will not oxidize copper.
It is such a powerful dehydrating agent, it can char many organic
substances (sugar dehydration-products are C and water)
heat
Little Tommy was my friend.
Alas, he is no more
What little Tommy thought was H2O,
Was H2SO4
24. Produced by the contact process-Sulfur is burned in air to form
sulfur dioxide, then sulfur dioxide combines w/more oxygen in
presence of vanadium(V)oxide to form sulfur trioxide; sulfur
trioxide combines w/water to form sulfuric acid
Dilute sulfuric acid combines w/ metals, oxides, hydroxides or
carbonates to form sulfate salts
Sulfuric acid and sulfates
25. Sulfuric acid and sulfates
Some important sulfates
Aluminum sulfate
26. Produced from Al2O3.2H2O (bauxite) 27. Used to treat water
28. Used to size paper - fill pores.Ammonium sulfate
29. Produced by reaction of H2SO4 and NH3 30. Used in fertilizers.