Mr. Sapalicio Physical science Monterey highlands elementary Ionic Bonds Ch. 5.2 Mr. Sapalicio Physical science Monterey highlands elementary

IOns An ION- an atom or group of atoms that has an electric charge. What?- atoms are generally neutral, once it loses or gains an electron it becomes an ion. Either a POSITIVE or NEGATIVELY charged ION.

IOns An ion is an atom or molecule where the total number of electrons is not equal to the total number of protons, giving it a net positive or negative electrical charge.

Polyatomic ions “Poly” means MANY. Therefore, polyatomic means many atoms. Some ions are made of several atoms. Ammonium ion is made of Nitrogen and Hydrogen atoms. FIGURE 8 QUESTION: How many electrons does a sulfur atom gain to become a sulfide ion?

What is an ion? An ion is an atom or group of atoms that has an electrical charge How does an atom become electrically charged? This happens when an atom either gains or loses valence electrons

Rules of valence electrons An atom with 1, 2, or 3 valence electrons will give away its extra electrons An atom with 5, 6, or 7 valance electrons will receive extra electrons

+ - When an atom gives away an electron it becomes a positive ion Becoming an ion When an atom gives away an electron it becomes a positive ion When an atom receives extra electrons it becomes a negative ion The positive and negative ions are attracted to each other forming a chemical bond called an ionic bond + -

The attraction between oppositely charged ions IONIC BONDS The attraction between oppositely charged ions Forms between metals and nonmetals compounds made from ions are called ionic compounds When these compounds form, the ions come together in a way to balance out the charges

Na Cl Na Cl Na Cl NaCl + - Sodium Chlorine Sodium ion Chloride ion has a 1+ charge Chloride ion has a 1+ charge NaCl Sodium Chloride ionic bond

Chemical formulas Chemical Formula- a combination of symbols that shows the ratio of elements in a compound. Ex: MgCl2 - Magnesium Chloride What does the formula tell you?

Formula’s of ionic compounds Answer: When ionic compounds form, the ions come together in a way that balances out the charges on the ions. The chemical formula for the compound reflects this balance. Subscript- tells you the ratio of elements in a compound. Ex: H20, CaCO3 If there is no subscript it is understood that it is one.

Naming Ion’s (optional info) CATION- positively charged ion ANION- Negatively charged ion

Naming Ionic Compounds Refer to pg. 185 The name of the positive ion comes first The positive ion is usually the name of the metal The name of the negative ion is second If the negative ion is a single element, the end of its name is changed to -ide If the negative ion is a polyatomic ion, the end of its name ends in -ite or –ate SO42- is sulfate

Properties of Ionic Compounds compounds have properties that are different from their constituents In general, ionic compounds are hard, brittle solids with high melting points When melted or dissolved in water , they conduct electrical currents vision learning chemical reaction

Ionic Crystals page 188 (right hand page in journal) 1. 2. 3. 4. On left hand page draw a picture of the ionic crystal on page 188 (figure 11)

Ionic Crystals page 188 (right hand page in journal) 1.form solids by building up repeating pattern of ions 2.The ions form a 3 dimensional arrangement called a crystal 3. Every Ion is attracted to ions of the opposite charge. 4.The pattern formed by the ions remains the same no matter what size of the crystal 5. Many crystals are hard and brittle On left hand page draw a picture of the ionic crystal on page 188 (figure 11)

High Melting Points 1. 2. 3. 4.

Electrical Conductivity 1. 2. 3.