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Unit 4, Lesson 2. Ionic and Covalent Bonding. Why Do Chemical Bonds Form?. Generally, atoms join to form bonds so that each atom has a stable electron configuration. Three basic ways that atoms bond:. Ionic Bonding Covalent Bonding (molecular bonding ) Metallic Bonding. Ionic Bond.
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Unit 4, Lesson 2 Ionic and Covalent Bonding
Why Do Chemical Bonds Form? • Generally, atoms join to form bonds so that eachatom has a stable electron configuration.
Three basic ways that atoms bond: • Ionic Bonding • Covalent Bonding (molecular bonding) • Metallic Bonding
Ionic Bond • Bonds that form from the attractions between oppositely charged ions. • Between a metal and a nonmetal
Covalent Bond • Atoms joined by covalent bonds share electrons. • Atoms may share more than one pair of electrons • Between a nonmetal and a nonmetal
Polar Covalent Bond • Atoms do not always share electrons equally. The bigger atom will tug on the smaller atom.
Metallic Bond • Bonding between metals • Metals are flexible and conduct electric current wellbecause their atoms and electrons can move freelythroughout a metal’s packed structure.
Polyatomic Atoms • A polyatomic ion acts as a single unit in a compound, justas ions that consist of a single atom do.
Some names of polyatomic anions relate to the oxygencontent of the anion
Determine if the following compounds are likely to have ionic or covalent bonds. methanol, CH3OH ionic ozone, O3 ionic covalent strontium chloride, SrCl2 covalent magnesium oxide, MgO
Draw the structural formula for acetylene, C2H2. • The atoms of acetylene bond in the order HCCH. Carbon and hydrogen atoms share two electrons, and each carbon atom must have a total of four bonds. How many electrons do the carbon atoms share?
Identifywhich two of the following substances will conduct electric current, and explain why. • aluminum foil • sugar, C12H22O11, dissolved in water • potassium hydroxide, KOH, dissolved in water Aluminum foil will conduct electricity because it is a metal and its valence electrons are free to move. KOH dissolved in water will conduct electricity because its ions are free to move.
Explainwhy electrons are shared equally in oxygen, O2, but not in carbon monoxide, CO. Because the atoms in a molecule of oxygen are the same, they attract and share electrons equally. Carbon and oxygen attract electrons differently, so electron sharing is unequal.
Predictwhether a silver coin can conduct electricity. What kind of bonds does silver have? Silver has metallic bonds so it has electrons that are free to move. The coin will conduct electricity.
Identifywhich of the bonds in calcium hydroxide, Ca(OH)2, are ionic and which are covalent. The compound contains an Ca2+ ion and 2OH- ions. These ions are held together by ionic bonds. OH- consists of covalently bonded oxygen and hydrogen ions.
Does dinitrogen tetroxide, N2O4, have covalent or ionic bonds? Explain how you reached your conclusion. Dinitrogen tetroxide has covalent bonds because both nitrogen and oxygen are nonmetals.
An atom of the element iodine, I, has much more attraction for electrons than an atom of strontium, Sr, does. What kind of bonds are likely to form between atoms of the two elements? Ionic bonds will form between iodine and strontium
How are metallic bonds similar to covalent bonds? How are they different? Metallic bonds are similar to covalent bonds in that electrons are shared between atoms. Metallic bonds are different from covalent bonds in that electrons are free to move around in the space between the atoms.