Chemical Bonding of Elements to each other.pptx

Study the types of bonding in elements.

1. Chemical Bonding

2. IONIC BONDING COVALENT BONDING PROPERTIES OF IONIC AND COVALENT BONDS

3. Bonding by transfer of electrons. This chemical bond only exists between metals and non-metals and that you need to consider metals from Groups 1 and 2 and the non-metals from the halogen group (Group 7). Ionic bonding

4. Ionic bonding is one of the most important types of  chemical bonding . It is responsible for the very existence of the  solid-state , which is a basis for all our physical and chemical properties.

5. The best way in choosing the combination that will form ionic bond is by computing the electronegativity difference between the two elements. (A combination which has an electronegativity difference of above 1.9 will result to ionic Bond.)

6. Electronegativity is the measure of the ability of an atom that is bonded to another atom to attract electrons to itself.  Elements  that attract electrons the most are found in the upper right corner of the table. Electronegativity increases across a period and decreases down a family. Fluorine is the most electronegative element with a value of 4. The least electronegative elements are Cesium and Francium in the opposite corner. The noble gases have zero electronegativity because their electron shells/energy levels are full.

7. Electronegativity is a unitless number; the higher the number, the more an atom attracts electrons.

8. Properties of Ionic Bonds

9. A strong force of attraction is present between the ionic bonds. Because of this force, we can observe several properties present in the Ionic bonds. Some of these Ionic bonds properties are as follows- Strength : Ionic bonds are formed when a metal atom loses one or more of its outer electrons and a non-metal atom acquires them. The metallic bond is formed by the attraction between the positively charged metal ions and the negatively charged electrons in the non-metal. The attractive force is called electrostatic force . The metallic bond is strong because of the strong attraction between two oppositely charged objects.

10. 2. Charge Separation : The ionic bond is the strongest and most reactive of the bonds. It forms when a metal atom loses one of its electrons, which moves over to a non-metal atom. The negative charge on one side attracts the positive charge, holding them together. For example, sodium chloride (table salt) is easy to dissolve in water because water molecules can move between the ions. They have enough energy to knock off an electron from a sodium atom or pull an electron away from a chlorine atom.

11. 3. High Melting & Boiling Points : The ionic bonded molecules have high melting and boiling point. Ionic compounds are compounds that contain ions. Ions are atoms or molecules with a net electrical charge because they have lost or gained electrons. The most common types of ionic bonds are electrostatic bonds, in which the negative electrons of an atom are attracted to the positive atomic nucleus of another atom.

12. Covalent Bonds

13. COVALENT BONDING It is also called a molecular bond . It involves the sharing of electron pairs between atoms. These electron pairs are known as shared pairs or bonding pairs, and the stable balance of attractive and repulsive forces between atoms.

14. A combination which has an electronegativity difference of less than 1.9 will result to covalent Bond.

15. As a general rule of thumb : C ompounds that involve a metal binding with either a non-metal or a semi-metal will display ionic bonding . Examples: S odium and chlorine will be ionic (a metal and a non-metal) Nitrogen monoxide (NO) will be a covalently bound molecule (two non-metals) silicon dioxide (SiO 2 ) will be a covalently bound molecule (a semi-metal and a non-metal) MgCl 2  will be ionic (a metal and a non-metal)

16. A polyatomic ion is an ion composed of two or more atoms that have a charge as a group (poly = many). The ammonium ion (see figure below) consists of one nitrogen atom and four hydrogen atoms. Together, they comprise a single ion with a 1+ charge and a formula of NH 4 + . The carbonate ion (see figure below) consists of one carbon atom and three oxygen atoms and carries an overall charge of 2−. The formula of the carbonate ion is CO 3 2− .

17. Compounds that contain covalent bonds (also called molecular compounds) exhibit different physical properties than ionic compounds. C ovalent compounds generally have much lower melting and boiling points than ionic compounds. For example, water (molecular compound) boils at 100 °C while sodium chloride (ionic compound) boils at 1413 °C. In fact, many covalent compounds are liquids or gases at room temperature, and, in their solid states, they are typically much softer than ionic solids. Furthermore, whereas ionic compounds are good conductors of electricity when dissolved in water, most covalent compounds, being electrically neutral, are poor conductors of electricity in any state.

18. The chemical formulas for covalent compounds are referred to as  molecular formulas  . Typically, a molecular formula begins with the nonmetal that is closest to the lower left corner of the periodic table, except that hydrogen is almost never written first (H 2 O is the prominent exception). Then the other nonmetal symbols are listed. Numerical subscripts are used if there is more than one of a particular atom. For example, we have already seen CH 4 , the molecular formula for methane.

19. Number of Atoms in Compound Prefix on the Name of the Element 1 mono-* 2 di- 3 tri- 4 tetra- 5 p enta - 6 hexa- 7 hepta- 8 octa- 9 nona - 10 deca - Numerical Prefixes for Naming Binary Covalent Compounds

20. Electronegativity is a unitless number; the higher the number, the more an atom attracts electrons.

21. ASSIGNMENT : 1. Make an emergency plan and prepare an emergency kit for use at home and in school.

22. OUTPUT # 2: MY INTERIOR OF THE EARTH 1. Create a creative diagram illustrating the behavior of seismic wave as it travels inside the earth . You can use different recyclable materials, cut outs pictures or draw/ paint your illustration. Printed outputs are not allowed.