Presentation on theme: "Chapter 5 Section 2 – Ionic Bonding and Salts"— Presentation transcript:
1Chapter 5 Section 2 – Ionic Bonding and Salts Because opposite charges attract, cations and anions should attractone another. This is exactly what happens when an ionic bond is formed.Ionic Bonds Form Between Ions of Opposite ChargeSalt: common word for ionic solidsRemember that sodium gives up its only valence electron to form astable Na+ cation. Chlorine, with seven valence electrons, acquiresthat electron. As a result, a chlorine atom becomes a stable Cl− anion.Na1e Na+Cl e-Cl-2-8-82-8-12-82-8-7Gives up 1 electron to chlorineGains the electron from sodium
2Chapter 5 Section 2 – Ionic Bonding and Salts The force of attraction between the 1+ charge on the sodium cationand the 1− charge on the chloride anion creates the ionic bond in sodiumchloride.Na Cl-IonicAttractionIonic Bond
3Chapter 5 Section 2 – Ionic Bonding and Salts All these salts are ionic compounds that are electrically neutral. Theyare made up of cations and anions that are held together by ionic bondsin a simple, whole-number ratio. For example, sodium chloride consists ofsodium cations and chloride anions bonded in a 1:1 ratio. To show this 1:1ratio, chemists write the formula for sodium chloride as NaCl.
4Chapter 5 Section 2 – Ionic Bonding and Salts However, the attractions between the ions in a salt do not stop with asingle cation and a single anion. These forces are so far reaching that onecation attracts several different anions. At the same time, each anionattracts several different cations. In this way, many ions are pulledtogether into a tightly packed structure. The tight packing of the ionscauses any salt, such as sodium chloride, to have a distinctive crystal structure.The smallest crystal of table salt that you couldsee would still have more than a billion billionsodium and chloride ions.
5Chapter 5 Section 2 – Ionic Bonding and Salts Ionic Compound PropertiesAlmost always form between a metal atom and nonmetal atomStronger the electronegativity difference the greater the ionic propertiesWill conduct electricity when a liquid or dissolved in water (aqueous)High melting and boiling pointsCrystalline structuresThey are not molecules (bonded compound between nonmetals)Hard and brittle
6Chapter 5 Section 2 – Ionic Bonding and Salts How to make an ionic compound conduct electricity.First you must know that electric current is when a charged particle isable to move. If the charged particle is fixed in place it is unable to conductcurrent.
7Li+ F- Al3+ Br- Cu2+ S2- Ni2+ P3- Sr2+ C4- Au3+ Se2- Cs+ O2- Pt4+ LiF Combine the following anions and cations for show the ionic compoundThat will form from each.Li+F-Al3+Br-Cu2+S2-Ni2+P3-Sr2+C4-Au3+Se2-Cs+O2-Pt4+LiFAlBr3CuSNi3P2Sr2CAu2Se3Cs2OPtO2
8Chapter 5 Section 2 – Ionic Bonding and Salts Review A white crystalline salt conducts electricity when it is melted and when it isdissolved in water. Which type of bond does this salt contain?1. ionic2. metallic3. covalent4. networkA chemical bond between two atoms results from a simultaneous1. attraction by the protons for the neutrons2. attraction by the two nuclei for the electrons3. repulsion by the valence electrons of the atoms4. repulsion by the protons in the two nucleiWhich formula represents a molecular substance?1. CaO2. CO3. Li2O4. Al2O3
9Chapter 5 Section 2 – Ionic Bonding and Salts Review Which compound contains ionic bonds?1. NO2. NO2 3. CaO4. CO2 If the electronegativity difference between the elements in compoundNaX is 2.1, what is element X?1. bromine2. chlorine3. fluorine4. oxygenWhich type of bond is formed when electrons are transferred from one atomto another?1. covalent2. ionic3. hydrogen4. metallic
10Chapter 5 Section 2 – Ionic Bonding and Salts Review The data table below represents the properties determined by the analysisof substances A, B, C, and D.Which substance is an ionic compound?1. A2. B3. C4. D