Element of the Dayhttp://www.youtube.com/watch?v=Q21clW0s0B8 La Lanthanum is a chemical element with the symbol La and atomic number 57. Lanthanum is a silvery white metallic element that belongs to group 3 of the periodic table and is the first element of the lanthanide series. It is found in some rare­earth minerals, usually in combination with cerium and other rare earth elements. Lanthanum is a malleable, ductile, and soft metal that oxidizes rapidly when exposed to air. It is produced from the minerals monazite and bastnäsite using a complex multistage extraction process. Lanthanum compounds have numerous applications as catalysts, additives in glass, carbon lighting for studio lighting and projection, ignition elements in llighters and torches, electron cathodes, scintillators, and others. Lanthanum carbonate (La2(CO3)3) was approved as a medication against renal failure. How many atoms of Lanthanum are in one mole of Lanthanum? How many grams are in one mole of Lanthanum atoms? 1 Chemistry 1. Element of the Day ­ La 2. Review Homework/Turn in Lab 3. Mystery Question 4. Continue Lecture 5. Finish The Mole POGIL 6. Start homework Announcements Due Today: Read pages 210 to 216 and answer questions 1, 3, 4, 5, and 7 on page 238. Also complete Lab Investigation Due Wednesday: Read pages 217 to 226 and answer questions 9, 11, 13, 17, 20, 25, 26, and 29. 2 Review Homework Questions 3 Mystery Question During our last laboratory investigation, we reacted copper (II) nitrate with sodium hydroxide to form copper (II) hydroxide and sodium nitrate. During the laboratory investigation we used approximately 37 milligrams of copper (II) nitrate and 12 milligrams of sodium hydroxide. For every molecule of copper (II) nitrate that reacts, how many molecules of sodium hydroxide react? At the end of the reaction, will there be any reactant leftover? If so, which and how much? copper nitrate 3.0 ml * 1l/1000ml * 0.1mole/l = 0.0003 moles * (63.546 + 14 + 48)g/mol = 0.037 grams sodium hydroxide 3.0 ml *1/1000ml * 0.1 mol/liter = 0.0003 moles * (23 + 16 +1)g/mol = 0.012 grams 4 Review Lecture: The Mole Names given to mathematical constants e googol googolplex mole Unit Order from smallest to largest 5 Lecture: The Mole Try finding a scale with amu... The gram is a much easier unit to use. Example: If a gold bar weighs 40.0 grams, how much would a silver bar weigh that has the same number of atoms? Mole (mol) is the number of carbon atoms in a 12.01 gram sample of carbon. This number, also known as Avogadro's number, is 6.022 * 1023. How big is this number? More Facts... A sample of an element with a mass equal to that element's average atomic mass expressed in grams contains 1 mol of atoms. Example 1: How much do 6.022*1023 atoms of Au weigh? Example 2: How much do 6.022*1023 atoms of Fe weigh? Example 3: How many moles are in a 5.0 gram sample of lithium? How many atoms are present? Example 4: 1 mol of H atoms has a mass of 1.008 g. How much mass does 1/2 a mol of H atoms contain (in grams)? 6 Lecture: The Mole Calculating Moles and Number of Atoms How many moles of atoms are found in a 12.0­gram sample of aluminum? How many atoms are there? Calculating the Number of Atoms A silicon chip has a mass of 3.01 milligrams. How many silicon atoms are present in this chip? Average atomic mass for silcon is 28.09 amu. 7 Lecture: The Mole Molar mass How can we calculate the number of atoms in or the mass of a compound? Example Carbon dioxide Picture Calculation Steps 1. Calculate the atomic masses of each element in the compound. 2. Add these masses together to find the molar mass (the amount of mass one mole of a substance). 8 http://www.youtube.com/watch?v=pNlmn7vbXBQ 9 Isopentyl acetate, C7H14O2 is a the compound released by bees when they sting. If a bee releases 1 microgram of this chemical, during a sting, how many molecules are released? 10 The Mole POGIL Activity Once finished, please start your homework. 11 Chemistry Lab Groups Group 1 Group 4 Matthew R Alderson Dominique D'Onofrio Spencer T Alpaugh Catherine E Edwards Daniel J Connelly Indigo M Larson Group 2 Group 5 Bill Lee Tiffany P Lee Anthony H McMillan Taylor Ahliquist Timothy D Taylor Dakota P Rice Sara Turpen Group 3 Annika J van Houte Aidan K Moore Martin W van Drunen 12 Exit Question How many atoms are in 0.5 moles of Au? Reminder Due Wednesday: Read pages 217 to 226 and answer questions 9, 11, 13, 17, 20, 25, 26, and 29. 13.