Chemistry Week 35 Please take a seat and get ready for lab day!

May 13, 2012 AGENDA: 1 – Bell Ringer & Agenda 2 – Lab Introduction 3 – Wash Hands 4 – M&Mium Decay Lab 5 – Post Lab Questions 6 – Turn in Lab 7 – Summary Today’s Goal: Students will be able to model radioactive decay through a lab investigation. Homework NONE! If you missed Friday’s Unit 7 Exam, you must come TODAY AFTER SCHOOL IN ROOM 301 to take it (Please be there by 3:30)!!

Monday, May13 th Objective: Students will be able to model radioactive decay through a lab investigation. Bell Ringer: In your own words, explain what the word radiation means?

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Monday, May13 th Objective: Students will be able to model radioactive decay through a lab investigation. Bell Ringer: In your own words, explain what the word radiation means?

May 13, 2012 AGENDA: 1 – Bell Ringer & Agenda 2 – Lab Introduction 3 – Wash Hands 4 – M&Mium Decay Lab 5 – Post Lab Questions 6 – Turn in Lab 7 – Summary Today’s Goal: Students will be able to model radioactive decay through a lab investigation. Homework NONE! If you missed Friday’s Unit 7 Exam, you must come TODAY AFTER SCHOOL IN ROOM 301 to take it (Please be there by 3:30)!!

Monday, May13 th SUMMARY: Scientists use the half-life of the radioactive isotope Carbon-14 to determine the age of fossils or artifacts from archeology sites. Based upon today’s lab, how do you think this process works?

Procedure 1. Wash Hands FIRST. I have soap, paper towels and hand sanitizer. 2. Count the number of M&Miums you have initially. 3. Place all into the cup, shake 2 or 3 times, then dump out onto paper. 4. Remove all M&Miums with the “m” side down, and put them aside. These atoms have decayed. 5. Count how many M&Mium have the “m” side up. These are the atoms that have not decayed. Put these atoms back into the cup. This represents 1 half-life. 6. Complete the steps above for half-lifes 2-5. Record all data. 7. Bring your group’s data up to me so I can compile the class data.

M&Mium Decay Data Half -- LifeGroup DataClass Data

1 st Period Lab Groups Amy Robert Arielle Mariama Quay Hydeia Shana Patricia Sara Isaiah Niamarion Carla Gerald Tumani Chronicle Ashanti Zahra Jane Imani Chibuzo Rahamanh Jasmine Danielle Kayla Kaylan Judy Maria Taylor Joy Rahamanh Tatiana Choice Justin 8

2 nd Period Lab Groups Chris Aginah Jenna Jared Regan Omari Ahzia Keira Keanthoy Joe Ajai Nathaly Camille Alan Javonte Jasmine Daija Sergio Ryan Tesia Otis Maya Najae Erick Angelique Kayla Lauryn Janiece

5 th Period Lab Groups Tyrese Courtney Romalle Tiara NeTanyah Tajana Darnell Destini Hunter Clarissa Kailah Jelani Dreshion Michael K Judah Jamille Kahlia Erik Savon Khamya Victoria Tanisha Jocelyn Khyri Badieye Michael G Murrell Chantice Breanna

6 th Period Lab Groups Jamie Tenisha Alex Jouet Julian Arya Cyntrall Nicole Jessica Jordin Michael Khalin D’angelo Erica Kyla Bria Teon Nanyamka Sydney Caylen D’niko Kihinde Ariel Tyler

8 th Period Lab Groups Keon Charles Abdul Patience Angela Ebony Brianna S Eric Paul Kennesha Nakia Sam Tayva Tamarha Carl Eriun Tiana Ravion Breanna R Jalaun Maya Sydney Willie Alexis Courtney Brittany David Elijah

Cornell Notes  Topic: Heat Curves and Heat Capacity  Date: 4/2/2013  Measuring energy: Universe = Surroundings + System SurroundingsSurroundings System HeatHeat EndothermicExothermic Review from yesterday q =(+) q =(-)

Cornell Notes Use this equation to calculate the heat released (q = neg.) or absorbed (q = pos.) when temperature is changing. q = m · C p · ∆T Use this equation if you are calculating the heat released (q = neg.) or absorbed (q = pos.) when substance is melting or freezing. q = H F · m Use this equation if you are calculating the heat released (q = neg.) or absorbed (q = pos.) when substance is boiling (evaporating) or condensing. q = H V · m When to use heat of fusion: When to use heat of vaporization: When to use heat capacity:

More Practice Problems (Show work on loose leaf paper) 1. What is the amount of energy need to vaporize 3500 g of water? 2. Calculate the amount of energy needed to melt 10 grams of mercury. 3. What is the amount of energy needed to vaporize 360 grams of butane. 4. What is the amount of energy released when 15 g of ether freezes. SubstanceH f (J/g) H v (J/g) Butane86414 Ether95392 Water Mercury Challenge: How many joules of energy are absorbed when 25g of steam cools from 100 o C to produce water at 10 o C? (2-step)

Cornell Notes  Topic: Review Heat Calculations  Date: 4/4/2013 Heat Capacity = the amount of heat required to change the temperature of an object (based on the specific heat). q = m · C p · ∆T  Units = J = g · (J/g°C) · °C Molar Heat of Fusion (H F ): the heat absorbed by one mole of a solid substance as it melts to a liquid at constant temperature. q = H F · m  Units: J = (J/g) · g Molar Heat of Vaporization (H V ): the heat necessary to vaporize (turn into a gas) one mole of a given liquid at constant temperature. q = H V · m  Units: J = (J/g) · g What is the heat of fusion? What is the heat of vaporization? What is heat capacity?

Cornell Notes How much heat does 10 g of water absorb if it is heated from 10°C to 25°C? q = m · C p · ∆T q = (10 g) ·(4.184 J/g°C)·(25 °C - 10°C) = J How much heat is released when 10 grams of water melts? q = H F · m q = (334 J/g)·(10g) = J How much heat is absorbed if 5 grams of water evaporates (boils)? q = H V · m q = (2260 J/g)·(60g) = 11,300 J Calculating using heat of fusion: Calculating using heat of vaporization: Calculating using heat capacity:

Cornell Notes Diagram Heat Curves. Solid Liquid Vapor/Gas Endothermic = system Melting Boiling To calculate heat, temperature is changing so you would use q = m · C P · ∆T To calculate heat, temperature is not changing so you would use q = H V · m

Cornell Notes Diagram Heat Curves. Solid Liquid Vapor/Gas Exothermic = system Freezing Condensing To calculate heat, temperature is changing so you would use q = m · C P · ∆T To calculate heat, temperature is not changing so you would use q = H F · m *Remember the sign of q will be opposite!