Thursday, November 29, 2012

Hunting the elements


Where do nature’s building blocks, called the elements, come from? They’re the hidden ingredients of everything in our world, from the carbon in our bodies to the metals in our smartphones. To unlock their secrets, David Pogue, the lively host of NOVA’s popular "Making Stuff" series and technology correspondent of The New York Times, spins viewers through the world of weird, extreme chemistry: the strongest acids, the deadliest poisons, the universe’s most abundant elements, and the rarest of the rare—substances cooked up in atom smashers that flicker into existence for only fractions of a second. If you want to know more about chemical elements and their importance in our world, I encourage you to watch this video

Tuesday, November 20, 2012

Fireworks



How do fireworks produce their colors and loud bangs?
Only chemicals are responsible for most of the spectacular effects. To produce the noise and flashes, an oxidizer is reacted with metal such as magnesium or aluminum mixed with sulfur. The resulting reaction produces a brilliant flash, which is due to the aluminum or magnesium burning, and the rapidly expending gases produce a loud report. For a color effect, an element with a colored flame is included. Yellows colors in fireworks are due to sodium; the red color is made by strontium; the green color is made by barium. Although you might think that the chemistry of fireworks is simple, achieving the vivid white flashes and the brilliant colors requires complex combinations of chemicals. 

Tuesday, November 13, 2012

Marie Curie Sklodowska


        Today, little bit about Poland and the Polish woman, Marie Curie Sklodowska (1867-1934), who opened the nuclear age. Marie Sklodowska, as she was called before marriage, was born in Poland in 1867. Both her parents were teachers who believed deeply in the importance of education. Since 1795, Poland was not listed on any map of the time because had been cut up and absorbed into three countries: To the east was Russia (including Warsaw); to the south was the Austrian Empire; and to the west was Prussia. Because of this situation, the Sklodowskis believed that Poland could become free only through the development of the mind—science—and through much hard intellectual work. Marie had her first lessons in physics and chemistry from her father. She had a brilliant aptitude for study and a great thirst for knowledge; however, advanced study was not possible for women in Poland. Marie dreamed of being able to study at the Sorbonne in Paris, but this was beyond the means of her family. To solve the problem, Marie and her elder sister, Bronya, came to an arrangement: Marie should go to work as a governess and help her sister with the money she managed to save so that Bronya could study medicine at the Sorbonne. When Bronya had taken her degree she, in her turn, would contribute to the cost of Marie's studies. When Marie was 35 years old with the degrees in physics and mathematics, she married Pierre Curie and both with a huge passion dedicated themselves to the science. As a result of their hard work, in 1903 the Curie’s won the Nobel Prize for their discovery of two elements radium Ra and polonium. 
But Marie Curie Skolodowska did not stop her research; she continued her work on radioactive elements and won the second Nobel Prize for chemistry for isolating radium and studying its chemical properties. After winning two Nobel Prizes she still  continued her researches into radioactivity up until her death from leukemia, due to many years of unprotected exposure to radiation at a time when its hazards were not yet known. Marie’s passion and persistence in science impress many people. What a woman!

Tuesday, November 6, 2012

Binary Compounds Type III



Hi
Cont’d of naming binary compounds. Today, we will learn how to name nonmetals together, which in chemistry is called Type III. First of all, we have to know which elements are nonmetals. All green elements are nonmetals.

The rules are very similar to binary compounds Type I and II
1.     Name the first element, using the full element name
2.     Name the second element with ending –ide
3.     Use prefixes to express numbers of atoms. Do not use mono – in first element
Prefix used to show numbers in chemistry.
Prefix
Mono              1
Di                    2
Tri                   3
Tetra               4
Penta              5
Hexa               6
Hepta              7
Octa                8

Example #1

BF3 first element is boron B, second element is fluorine F, but according the rule#3 we have to change the ending (–ide) for second element, therefore we have fluoride. Now, B has one atom (we don’t need to indicate the one atom as B1,) which means mono but as rule # 3 says do not use mono in first element. The second element is F with has 3 atoms, so you have to use prefix tri before the name – trifluride.
The full name for BF3 is boron trifluride.

Example #2

P2Cl5;  P = phosphorus, Cl = chlorine. We have 2 atoms of P= diphosphorus, and 5 atoms of chlorine= pentachloride; don’t forget to change the ending for - ide. The full name for P2Cl5  is diphosphorus pentachloride

Thursday, November 1, 2012

Binary Compounds Type II


This post is a continuation of scrambling your brains with naming compounds. So far we know that binary ionic compounds Type I contain metals that always give the same cation. For example, Lithium always forms the Li 1+, Magnesium forms the Mg 2+ , and Aluminum always forms the Al 3+. However, there are many metals that can form more then one type of cation. For example, Iron can be Fe 2+ or Fe 3+ and Chromium can be Cr +2, Cr +3, or Cr +6 . Because those metals can have different charges, we need to identify, which cation is present in compounds containing metals that can form more than one type of cation. Therefore, chemists used a Roman numeral to specify the charge on the cation. The rules for naming those compounds are called binary ionic Type II compounds and they are very similar to Type I.
Rules
1. The cation is always named first, and the anion second.
2. The cation is name after the element.
3. The anion is name by taking the first part of the element name and adding –ide.
4. Use a Roman number to specify the charge on the cation.

Examples
Compounds of iron and chlorine
Fe Cl, where Fe can have charge +2 or +3 and Cl is always -1.
Fe ? Cl -1  to balance them to 0, we need to have on both sides  Fe +2 and Cl -2 or Fe +3 and Cl -3  so what do we need for both sides?
If we want to have charge +2 for iron we need to have charge -2 for chlorine, the compounds will look like that FeCl2; let’s check if the elements are balanced to 0.
+2     -1   charges
Fe1Cl2; Fe +2 times 1(single Fe has one atom you don’t need to write the 1)= positive two, and Cl -1 times 2 = negative two. The name of the compounds is iron (II) chloride
if we want to have charge +3 for iron we need to have charge -3 for chlorine, the compounds will look like that FeCl3; let’s check it the elements are balanced to 0.
+3     -1
Fe Cl3 ; Fe +3 times 1= positive 3 and Cl -1 times 3= negative 3. The name of the compounds is iron (III) chloride.

Well naming compounds may seem difficult but practicing problems will make you a master.