11/18 & 11/19 - 8th Grade Agenda Learning Objective: Bonding in Metals Collect HW: Reading & Notetaking: p.100 – 101 Video: Science Fair Project Textbook Reading p.198-203 HW: Reading & Notetaking p.103 – 104 Reminder HW: Science Fair Topic due 12/2 & 12/3 (10 Points)
Daily Reflection Prompt: Write difference between ionic and covalent bonds
Covalent Bond Chemical bond formed when two atoms sha_____ electron is called a covalent bond. Covalent bonds usually form between atoms of nonme_____ In contrast, ionic bonds form when metal and nonmetal combine re tal
What is a Covalent Bond? A chemical bond formed when two atoms share electrons is called a covalent bond
Examples of Covalent bonds
What are the characteristics of Molecular Compounds (Covalent Bonds) Lower melting point that Ionic compounds Lower boiling point that Ionic compounds Poor conductors of electricity
What is a difference between an Ionic Bond and a Covalent Bond? In an Ionic Bond, Chemical bond is formed by atoms loose electrons and becoming ions In Covalent Bond, chemical bond is formed when atoms share electrons
Ionic vs Covalent Bond Ionic Bond Covalent Bond
Is Salt (NaCl) a Ionic or Covalent Bond? Ionic Bond
Is Water a Ionic or Covalent Bond?
What are the characteristics of Molecular Compounds (Covalent Bonds) Lower melting point that Ionic compounds Lower boiling point that Ionic compounds Poor conductors of electricity
What is a Double Bond? Double Bond is a covalent bond where two pairs of electrons are shared
What is a Triple Bond? Triple Bond is a covalent bond where three pairs of electrons are shared
Polar Molecule - Water What is the charge of the Hydrogen side of the molecule? What is the charge of the Oxygen side of the molecule?
Polar vs. Non Polar Molecule
Why don’t water and vegetable oil mix? Oil is nonpolar, water is polar. Nonpolar and polar compounds do not mix well together.
When you do laundry, what causes the nonpolar dirt to mix with the polar water? Detergent causes the dirt and water to mix
Steel = Iron + other metals What is an alloy? An alloy is a mixture made of two or more elem______, at least one of which is a metal. Alloys are generally stron_______ and less reactive than the pure metals from which they are made ents Steel = Iron + other metals ger Brass = Copper + Zinc
Which one is stronger? Pure gold or Gold alloy? Gold Alloy is stronger
What is Alchemy? More than thousand years ago, some people came up with a idea to turn cheap lead metal and turn it into gold by adding acid to it. Question: Is that possible? Answer: No.
Why can’t one element be made into another element by a chemical reaction? Because chemical change involves the electrons but doesn’t affect the nucleus. Since the number of protons determines the identity of the atom, one element can’t be made into another element by a chemical reaction.
What is the symbol for Gold? Au Someone grabs your gold chain and you say A-u give me back that gold
What is the symbol for Silver? Ag As I Age my hair turns silver
What is the symbol for Sodium? Na Na, I don’t want any salt.
What is the symbol for Potassium? K The first three letters of potassium is pot. Pots are also named Kettles
What is the symbol for Iron? Fe The giant pumping iron says Fe fi fo fum.
Symbols you need to know for the Test H = Hydrogen He= Helium Li = Lithium Be = Beryllium B = Boron C = Carbon N = Nitrogen O = Oxygen Na = Sodium K= Potassium Fe = Iron Ag = Silver Au = Gold