The chemical connection.pptx

valence electron

1. The chemical connection

2. The lewis electron dot structure A Lewis Structure is a very simplified representation of the valence shell electrons in a molecule. It is used to show how the electrons are arranged around individual atoms in a molecule. Electrons are shown as "dots" or for bonding electrons as a line between the two atoms. 

3. Gilbert Lewis was an American physical chemist whose concept of electron pairs led to modern theories of chemical bonding. He was able to formulate a system in which atoms combine to achieve a more stable electron configuration after the development of periodic table.

4. The outer region of the atoms are the ones in contact in chemical bond . A single electron or two or more electrons in the outermost energy level of an atom is called the valence electron. The valence electron is the one responsible for chemical properties of the atom.

5. Gilbert lewis was an American chemist who devised a system of dots called the lewis electron dot structure. This system uses the symbol of an element and one dot to represent each valence electron. The number of valence electrons is important in determining the number of bonds an atom will form, the number of unpaired electrons, and an atom;s formal change.

6. The group number indicates the number of electrons in an element’s outermost energy shell. Also, the period number indicates the number of shell of an element. For example, all the elements in group 1A (1) have one velence electron. Moreover, all the elements in group 2A have 2 velence electrons. The same rules applies to group 3A (13), 4A(14), 5A(15), 6A(16) and 7A(17)or the representative elements. During chemical bonding, an atom needs to attain eight electrons in its outermost energy level to become stable according to the octet rule .

7. Electron affinity and electronegativity Electronegativity refers to the ability of the atoms to attract electrons from the other elements. Electron affinity refers to the amount of energy that is liberated whenever a molecule or a neutral atom tends to acquire an electron from the other elements. It is applied only to a single atom

8. During chemical bonding, the electrons in the outermost energy level of atoms interact with other electrons of other atoms. The ability to accept one or more electrons is another property that greatly influences the chemical behaviour of atoms. This called electron affinity . If the electron affinity of an atoms is more positive, then the element has a greater tendency to accept electrons.

9. electronegativity Electronegativity is the ability of an atom to attract electrons with molecules (bonded atoms) rather than a free electron. In the periodic table, the electronegativity of an atom generally increases from left to right across periods, and increases bottom to top (or decreases as you go down) in groups.

10. Both electron affinity and electronegativity play an important role in the chemical bonding properties of elements. Linus Pauling introduced the concept of electronegativity and created the electronegativity chart value where the elements on the top right side of the periodic table are more electronegative. Element belonging to group 1A and 2A are less electronegative elements. This means that fluorine (F) has the highest ability to attract more electrons when bonded . The difference in the electronegativity of the elements predict the type of bond that will take place.

11. “like electrons, people have a tendency to lose things or gain things from another as a result of their bonding and interaction to satisfy their needs.”