Electron Configuration and the Periodicįigure 5.11 again shows the periodic table but without the symbols of the elements. Thus the elements in column 8 are known as the family or group of noble gases.Ī. The elements in a column make up a family of elements. In the middle of the table, have not been numbered.įIGURE 5.10 Periodic table of the elements. The table so that the table will fit into a reasonable space. These two displays are customarily put below Again, in some tables actinium is the first Similarly, theĭisplay labeled 'actinides' belongs in period 7 between element 89 (actinium)Īnd element 104 (rutherfordium). Tables, lanthanum is the first member of the lanthanide series. Of elements labeled 'lanthanides' and placed below the table belongs in periodĦ between element 57 (lanthanum) and element 72 (hafnium). Rows are called periods and each period is numbered. Seven rows are used to show all of the elements now known. In the table, the elements are placed in rows and columns of Section we will show how the various features of the table relate to the electronĬonfiguration of the different elements and to their position in the table.įirst let us point out those features using the complete periodic table shown We also pointed out that theĭesign of the periodic table separates the metals from the nonmetals. The noble gases and helium are all 'happy,' because their valence shell is full.Table was introduced as a list of the elements. Even though it only has two electrons, it is still grouped with the noble gases that have eight electrons in their outermost orbitals. It is very stable with only two electrons in its outer orbital (valence shell). Helium (He) is different from all of the other elements. Your chemistry work will most likley use molecular hydrogen (H 2) or hydrogen ions (H +, protons).

Atomic hydrogen wants to combine with other elements to fill its outer shell. You probably won't find atomic hydrogens floating around by themselves. There is only one electron and one proton. Hydrogen, in its neutral form, does not have a neutron. Hydrogen (H) and helium (He) are special elements. However, because the atomic number for phosphorus is fifteen, the electron configuration is 2-8-5. Phosphorus (P) is also in Group VA which means it also has five electrons in its outer orbital. All of that information tells you there are two electrons in the first orbital and five in the second (2-5). The 'V' is the Roman numeral for five and represents the number of electrons in the outer orbital. How many electrons are in its outer orbital? Nitrogen is in the fifteenth column, labelled 'Group VA'. The atomic number tells you there are seven electrons in a neutral atom of nitrogen. Transition elements add electrons to the second-to-last orbital.įor example, nitrogen (N) has the atomic number seven. There are exceptions to the order when you look at the transition elements, but you get the general idea. As you keep counting the columns, you'll know how many electrons are in the outer shell. Every element in the second column (group two) has two electrons in the outer shell. They are the electrons involved in chemical bonds with other elements.Įvery element in the first column (group one) has one electron in its outer shell. Those outer electrons are also called valence electrons. The elements in each group have the same number of electrons in the outer orbital. The periodic table also has a special name for its vertical columns. Now you know about periods going left to right. At this time, there is a maximum of seven electron orbitals. As you move down the table, every row adds an orbital. All of the elements in the second row (the second period) have two orbitals for their electrons. For example, every element in the top row (the first period) has one orbital for its electrons.

All of the elements in a period have the same number of atomic orbitals. When you look at the periodic table, each row is called a period (Get it? Like PERIODic table.). Magnesium and sodium (Na) also share qualities because the are in the same period (similar electron configurations).Įven though they skip some squares in between, all of the rows read left to right. For example, magnesium (Mg) and calcium (Mg) are found in column two and share certain similarities while potassium (K) and calcium (Ca) from row four share different characteristics. Each row and column has specific characteristics. As with any grid, the periodic table has rows (left to right) and columns (up and down). Each element is placed in a specific location because of its atomic structure. The periodic table is organized like a big grid.

Valence electron periodic table list