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Element of the Day La Lanthanum Is a Chemical Element with the Symbol La and Atomic Number 57

Element of the Day La Lanthanum Is a Chemical Element with the Symbol La and Atomic Number 57

Element of the Dayhttp://www.youtube.com/watch?v=Q21clW0s0B8 La Lanthanum is a with the symbol La and 57. Lanthanum is a silvery white metallic element that belongs to 3 of the and is the first element of the series. It is found in some rare­earth minerals, usually in combination with and other rare earth elements. Lanthanum is a malleable, ductile, and soft that oxidizes rapidly when exposed to air. It is produced from the minerals and bastnäsite using a complex multistage extraction process. Lanthanum compounds have numerous applications as catalysts, additives in , carbon lighting for studio lighting and projection, ignition elements in llighters and torches, cathodes, , and others. Lanthanum (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 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

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.

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