Thursday, October 25, 2012

Binary Compounds Type I


Hi everyone
Here is a head scrambler for you, which is naming compounds. Today, I will show you how to name two elements together; in in the scientific language we called this binary compounds type I. Binary compounds type I is about connecting elements that can form only one type of cations with elements that form anions. The rules are simple,
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.
Here are common simple cations and anions.


Examples

What is the name of Li  - lithium (+1 charge) and F – fluorine (-1 charge)?

Li is a cation with charge +1, and F is an anion with charge -1.
Li++F- = LiF
The name of the compounds is lithium fluoride

What is the name of K potassium and I iodine?
K is a cation with charge +1, and I is an anion with charge -1.
K++I- = KI
So the name is potassium iodide

As you see from these examples, the charges on cations and anions are the same +1 and -1, to give the zero net (because -1 +1 = 0), but what happen it the charges are different like +2 and -1? Well, we have to balance them to zero, but the naming rules are the same.

Examples

What is the name of Mg magnesium  (+2 charges) and Br bromine (-1 charge)?
+2            -1
Mg + Br= MgBr2     
Mg has +2 charges and bromine -1 charge. To have zero net, we have to multiply -1 Br times 2 to have -2 (because +2 and – 2 is zero) therefore we have Br2
The name of the compounds is magnesium bromide

What is the name of Na sodium (+1 charge) and O oxygen ( -2 charges)?
The name is sodium oxide, but the formula is
 
+1         -2
Na + O= Na2

Friday, October 19, 2012

Ions, Cations, and Anions



          Today, I will discuss the differences between ions, cations, and anions. From the last post about the structure of atoms, we know that an atom has the same number of electrons (negative charge) and protons (positive charge) to make the atom in an exact balance (neutral atom). What happens when an atom has extra electron or missing electron? The atoms are called ions.
So, when you are missing an electron or two, you have a positive charge called cation. When you have an extra electron or two, you have a negative charge called anion.

An example of creating cation.


A neutral lithium (Li) has 3 protons and 3 electrons, and it is missing an electron. Then we have 3 protons and 2 electrons. So lithium loses one electron to become a 1+cation.

An example of creating anion.
                                        
A neutral chlorine Cl has 17 protons and 17 electrons, and it is gaining one electron. Then we have 17 protons and 18 electrons. So, chlorine gained one electron to become a 1- anion.

Thursday, October 11, 2012

The Structure of the Atom


Hi everyone 
Last time I discussed the organization of the periodic table. As we know the periodic table contains 118 elements. Each element has a name, symbol, weight, and atomic number. So, all matter (everything what is around us) is made of elements (atoms). An atom is like a tiny solar system. In the center of the atom is the nucleus, which is a group of protons and neurons. The protons have a positive electric charge while the neutrons are electrically neutral. The nucleus makes up almost all of an atom’s mass or weight. Spinning at fantastic speeds around the nucleus are smaller and lighter particles called electrons that have a negative electric charge.  An atom has the same number of electrons (negative charge) and protons (positive charge) to make the atom in an exact balance—it has zero net charge.
For example
A Carbon C atom has six protons in its nucleus and six electrons outside its nucleus, which mean the element has zero net charge.

Thursday, October 4, 2012

Introduction to the Periodic Table


In any classroom where chemistry is taught there is a big chart called the periodic table, and we also have one in my classroom’s wall. This week the real chemistry began, and I learned the organization of chemical elements. The periodic table has 118 boxes, which contains a symbol and number of the element. The boxes are place in horizontal order of increasing number (they are called a proton or atomic number). Also, the elements are place in vertical way called groups, which mean they have similar chemical properties. The first group has the name alkali metals; the second group is called alkaline earth metals. Next we have couples groups of transition metals, metalloids group, chalcogens, halogens, and noble gases group. In an easier way, we can divide all the elements on metal and not metal.
Below there are two pictures.
1. The elements classified as metals and as nonmetals.



2. The more specified organization of the elements