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Name:
Sodium - cation (+ ion)
Symbol:
Na
Atomic Number:
Atomic Mass:
11
22.98976928
Family: Group 1 (IA) :
alkali metal
Oxidation states:
+1, -1 (strongly basic oxide)
Molar mass:
electronegativity:
bond type:
Pronunciation:
2.3 X26 g/mol
0.93
Metallic
SO-dee-um
Sodium is a member of the alkali metals family. The alkali family consists of elements in
Group 1 (IA) of the periodic table. The periodic table is a chart that shows how chemical
elements are related to one another. Other Group 1 (IA) elements are lithium, potassium,
rubidium, cesium, and francium. The members of the alkali metals family are among the most
active elements. Compounds of sodium have been known, of course, throughout human history.
But sodium metal was not prepared until 1807. The reason is that sodium attaches itself very
strongly to other elements. Its compounds are very difficult to break apart. It was not until 1807
that English chemist Sir Humphry Davy (1778–1829) found a way to extract sodium from its
compounds. Sodium metal itself has relatively few uses. It reacts with other substances easily,
sometimes explosively. However, many sodium compounds have a variety of uses in industry,
medicine, and everyday life.
Physical Properties:
Sodium is a silvery-white metal with a waxy appearance. It is soft enough to be cut with a
knife. The surface is bright and shiny when first cut, but quickly becomes dull as sodium reacts
with oxygen in the air. Sodium’s melting point is 208.1°F (97.82°C) and its boiling point is
1,618°F (881.4°C). Its density is slightly less than that of water, 0.968 grams per cubic
centimeter. Sodium is a good conductor of electricity.
Chemical Properties:
Sodium is a very active element. It combines with oxygen at room temperature. When
heated, it combines very rapidly, burning with a brilliant golden-yellow flame. Sodium also
reacts violently with water. The effect is fascinating. When sodium metal is first placed into
water, it floats. But it immediately begins to react with water, releasing hydrogen gas.
Chemical Reaction with Oxygen:
Na(s)+O2(g) ----> Na2O(s)
4Na(s)+O2(g)-----> 2Na2O(s)
Sodium Chloride, or table salt:
2Na(s) + Cl2(g) ——> 2NaCl(s)
Limiting Reaction
4Na(s)+O2(g)-->2Na2O(s)
100 g Na (1 mol Na/23g Na) (2mol N/4mole Na)(62 g Na2O/1mol Na2O)=134.7 g of Sodium
Oxide, limsting reagent.
Isotopes:
There is only one naturally occurring isotope of sodium: sodium-23. Sixteen radioactive
isotopes of sodium with measured half lives are also known. Two radioactive isotopes of
sodium—sodium-22 and sodium-24— are used in medicine and other applications. They can be
used as tracers to follow sodium in a person’s body. A tracer is a radioactive isotope whose
presence in a system can easily be detected. The isotope is injected into the system at some point.
Inside the system, the isotope gives off radiation. That radiation can be followed by means of
detectors placed around the system. Sodium-24 also has non-medical applications.
work cited
"Sodium." Chemicool Periodic Table. Chemicool.com. 18 Oct. 2012. Web. 12/10/2012
<http://www.chemicool.com/elements/sodium.html>.
Bentor, Yinon. Chemical Element.com - Sodium. Dec. 10, 2012
<http://www.chemicalelements.com/elements/na.html>.