1.65k likes | 1.83k Views
C: 4 January 2012. Grab a calculator and find your new seat. Objective : You will be able to: convert between number of atoms/molecules, moles and mass of any element or compound. Do now : Search in your notes: a. What is a mole? b . How many atoms/molecules are in a mole?. Agenda.
E N D
C: 4 January 2012 • Grab a calculator and find your new seat. • Objective: You will be able to: • convert between number of atoms/molecules, moles and mass of any element or compound. • Do now: Search in your notes: • a. What is a mole? • b. How many atoms/molecules are in a mole?
Agenda • Do now • Review: The Mole • Mole to atoms/molecules conversions • Practice Problems • Mole to mass conversions • Practice Problems Homework: Week 17 Homework page 1-2: tomorrow Hey, did I get your lab report?!
Calculators • You’re going to need a calculator to complete homework for the rest of the year. • Come work in here Tues. and Thurs. • Buy a $10 scientific calculator • must have scientific notation • Use your cell phone (at home).
The Mole • Atoms are so tiny; how do we quantify their masses? • The mole: a unit for amount of substance • In groups of 6.02 x 1023 atoms or molecules • 6.02 x 1023 atoms/molecules = 1 mole • 6.02 x 1023 atoms/molecules = Avogadro’s Number
Big Questions • http://www.youtube.com/watch?v=s0zxF66nbRU • If you react 5.0 grams of oxygen with 5.0 grams of hydrogen, what will you produce? • How many grams will be produced? • Will there be oxygen or hydrogen left over? • If so, how much?
Convert Between Moles and Number of Atoms/Molecules Same two fractions for ANY element or compound!!
Example 1 • How many atoms of silver are in 5.00 moles of silver?
Example 2 • How many molecules of water are in 3.5 moles of water?
Example 3 • How many moles of sodium are equal to 1.50x1024 atoms of sodium?
Example 4 • How many moles of water are equal to 5,000.0 molecules of water?
Practice Problems • Convert 3.01 x 1023 atoms of silver to moles. • Convert 2500 molecules of water to moles. • How many atoms of carbon are in 3.2 moles of carbon? • How many atoms of beryllium are in 2.1x1014 moles of beryllium?
Homework • Week 17 Homework page 1 • and…did I get your lab report?!
Atoms to Moles • How many atoms of sodium are in 0.5 moles of sodium? • How many atoms of oxygen are in 1.5 moles of oxygen? • How many atoms of fluorine are in 0.075 moles of fluorine? • How many atoms of argon are in 3.45 moles of argon?
C: 5 January 2012 • Take Out Homework: Week 17 p. 1 • Objective: You will be able to: • convert between mass and number of moles of a sample of any element or compound. • Do now: How many moles are equal to 2,300,000 molecules of methane? Show your work!
Agenda • Do now • Homework answers • Review converting between moles and number of atoms/molecules • Converting between moles and mass of elements and compounds • Practice Problems • Ticket • Moles Conversions Stations Homework: Week 17 Homework page 2: Fri. Quiz Monday on atom/molecule, mole, mass conversions
Converting between moles and mass of elements • Two possible conversion fractions:
Example 1 • Calculate the mass in grams of 3.50 moles of hydrogen.
Example 2 • Calculate the number of moles equal to 10.0 grams of silicon.
Practice Problems • What is the mass in grams of 3.50 mol of copper? • What is the mass in grams of 2.25 mol of iron? • How many moles of aluminum are equal to 11.9 grams of aluminum? • How many moles of calcium are equal to 5.00 grams of calcium?
What if you’re working with a compound, not an element? • Mass = molar mass! • Review: Calculate the molar mass of water.
Example 1 • Calculate the mass of 3.0 moles of water.
Example 2 • Calculate the number of moles equal to 0.50 grams of carbon dioxide.
Converting Between Moles and Mass • Calculate the mass of 5.00 moles of methane. • Calculate the number of moles equal to 5.00 grams of boron trifluoride. • Calculate the mass of 0.50 moles of ammonia (NH3). • Calculate the number of moles equal to 1,000. grams of water.
Objective Ticket • Start your homework if you finish early.
Homework • Week 17 Homework page 2: Fri. • Quiz Mon. on atom/molecule, mole, mass conversions
C: 6 January 2011 • Grab a calculator • Take Out Homework: Week 17 p. 2 • Objective: You will be able to: • convert between number of atoms/molecules, moles and mass of a sample of any element or compound. • Do now: Calculate the mass of 5.00 moles of magnesium chloride (MgCl2).
Agenda • Do now • Check homework • Finish conversion stations Homework: Week 17 page 3-4: Mon. Quiz Monday on atom/molecule, mole, mass conversions
Mass to moles to atoms lab • On the front: • Find the mass of the sample. Subtract the mass of the container (given on the card). • Convert to moles • Convert to number of atoms • Always show all your work! • A correct answer = a number + units + element/compound
On the back: • Copy down the number of atoms (from the card) • Convert to moles • Convert to mass • Check your answer by massing the sample on the balance.
C: Homework • Week 17 Homework p. 3-4: Mon. • Quiz Mon. on atoms/molecules, moles, mass conversions
C: Homework • Week 17 Homework p. 2: tomorrow
C: 9 January 2012 • Grab a calculator and your green folder • Take Out Homework: Week 17 p. 3-4 • Objective: You will be able to: • convert between atoms/molecules, moles and mass of any element or compound. • Do now: How many atoms are there in 1.00 gram of zinc? (Do this in two steps.)
Agenda • Do now • Homework answers • Questions • Quiz on 4.1 and 4.2 • Hand back work/progress reports/clean out folders • Demo: chemical change Homework: None!
Quiz • When you finish, raise your hand. • Track your last Unit 3 Quiz • Clean all Unit 3 materials out of your folder and paperclip them together, with your tracking sheet on top. • Leave this pile on your desk for stamps. • Then, after the quiz, put it in your green folder.
C: 12 January 2012 • Grab your green folder • Objective: You will be able to: • write correct formula equations for chemical reactions • Do now: Brainstorm: Write down as many indications (signs) of a chemical reaction as you can.
Agenda • Do now • Organize/stamp • Chemical reactions notes and demo • Writing equations examples • Practice problems Homework: Week 18 Homework #1-3, 7-9: Fri. Late work/Lab report rewrites by Weds. Jan. 18
10 min. to organize • Organize your folder/notebook. • Stack up and paperclip all Unit 3 materials Put your tracking sheet on top. • Track your last Unit 3 Quiz. • Get stamps! • Put your papers in your green folder in the bin. **You must be in your seat unless you are putting your folder in the bin.**
Demo • In your notebook, record your observations.
Indications of a Chemical Reaction • Heat and Light • Production of a Gas (bubbles) • Formation of a precipitate • A solid produced as a result of a reaction between two solutions • Color change
chemical reaction: changing substances to other substances by breaking bonds in reactants and forming new bonds in products.
Chemical Equations • How do chemists describe chemical reactions? • chemical equations: an expression representing a chemical reaction
Word Equation • Hydrogen gas combines (explosively!) with oxygen gas to produce water vapor • reactants: hydrogen, oxygen • products: water
Formula Equations • H2(g) + O2(g) H2O(g) • (s) – solid, (l) – liquid, (g) – gas • (aq) – aqueous (dissolved in water) Reactants Products
Symbols • + and, reacts with • yields (to yield), produces (to produce), forms (to form)
Diatomic molecules • 7 elements make diatomic molecules: • H2, N2, O2, F2, Cl2, Br2, I2 • “7 make a 7” • HINClBrOF
You must be sure to write correct chemical formulas for reactants and products!
Write the word equation • Na2O(s) + H2O(l) NaOH(aq) • Solid sodium oxide reacts with water to yield a solution of sodium hydroxide
Write the formula equation • Solid copper reacts with a solution of silver nitrate to yield solid silver and a solution of copper (II) nitrate. • Cu(s) +AgNO3(aq) Ag(s) + Cu(NO3)2(aq)