Chemistry lab Pennium and Candium

Chemistry Lab Pennium Lab 

Purpose
In this lab you will investigate the concept of atomic mass and how it was derived.You will develop your own unit of measure,the CMU,amd use it to measure the relative masses of other coins.At the conclusion of this lab you will be able to explain how scientists developed the system for AMU's (atomic mass unit) and how it is applied to determine the relative masses of other atoms of other elements

Procedures part 1
 1) Obtain a packet of pennies.
2) Sort the pennies into two groups: pre 1982 and 1982 and newer.
3) Measure the mass (in grams) of each stack of pennies. Record the mass (in grams) of each penny stack in a data table. Count the number of pennies in each stack.
4) Measure the mass in grams of a half dollar, quater, nickel, and dime. Record these values in a data table.
5) Answer the questions below and then continue with Part 2.

Questions part 1

1) Does each penny have the same mass?
2) Can you identify two "penny isotopes" based on masses of the pennies? Explain.
3) What does your data tell you about the relationship between mass of a penny and date of a penny. Make a generalization.

Procedures part 2

1) Determine the average mass of pre-1982. (Record Average)
2) Determine the average mass of post-1982. (Record Average)
3) Determine the percentage of your pennies that is pre-1982 and the percentage that is post-1982. These percents should add up to 100%. What you have calculated is the percent abundance of each group of pennies (penny isotope).
4) Let's choose one of your coins to make a CMU (coin mass unit). Let's say that  the mass of a nickel (Fivecentium), quarter (Quarterium), dime (Dimeium), pre-82 pennies (Pre-82 Pennium), post-82 pennies (Post-82 Pennium). Again, show all calculations, and record all data in a data table.
5) Determine the average mass of Pennium in CMU's using the percent abundance (from #3) of each pennium isotope (pre-82 and post -82) and the mass of each pennium isotope in CMU's (from #4).

Questions and Conclusion Part 2 

1) Make a statement about the average penny mass of pre-82, post-82, and pennies in the packet.
2) Explain how you derived the unit "CMU".
3) Using the idea you explained in #2 above, how did scientists obtain the Atomic Mass Unit (AMU) to measure the ass of atoms of different elements?
4) What is your weight in CMU's? (Remember 1 lb = 2.205 Kg)
5) Write a statement that compares what you did in this lab to what scientists have done to find the average atomic masses of the elements. 

Pre 1982	Post 1982	Nickel	Dime	Qaurter
Mass	2.5	3.04	5	2.3	5.7
Relative Abundance	11	14	1	1	1
Average Mass	.5g	.61g	1g	.46g	1.14g

Candium lab

Purpose

• To use Candium model to explain the concept of atomic mass
• To analyze the isotopes of Candium and calculate it's atomic mass

Materials

• Sample of candium
• Balance

Procedure

Candy	Gobstoppers	M&M's	Skittles	Sixlets
Avg mass of each	1.67	.87	1.08	.81
% abundance	.19	.26	.21	.32
Relative abundance	9	13	11	15
Relative mass of each	2.07	1.09	1.35	1
Avg Mass of all	1.11	1.11	1.11	1.11

1. Obtain sample of Candium'
2. Separate it into its 3 isotopes.(Peanut M&ms,reese,skittles)
3. Determine the total mass or each isotope
4. Count the numbers if each isotop                                                                                                            Record data and calculations in the data table create a data table that has the following:

  1.Average mass of each isotope

  2.percent abundance of each isotope

  3.relative mass of each isotope

  4.average mass of all isotopes

  5.relative abundance of each isotope
  Your data table should have five columns and seven rows

Discussion

1.Summarize what you did

2.Define the term isotope

3.Explain the difference between percent abundance and relative abundance.

(What is the result when you total the individual percent abundance values for each isotope?

   What is the result when you total the individual percent relative values for each isotope?

4.Compare the total values for rows 3 and 6 in data tables.How does the average mass differ from relative mass?

5.Compare your value for relative mass to that of that class.

6.Comment on your percent error,sources of error in the activity,and provide suggestions for improvement.

7.Comment on how the activity is a model for calculating atomic mas of real elements.  

-Conclusion-







In order to get exact results on this activity, be sure to round correctly and read your scale right. Also, if you measure your candy in a cup or a bag be sure to subtract the weight of the container from what the triple-beam-balance says, or else all your calculations will be off from the beginning. This activity is a model for calculating atomic masses of real elements because it gives everyone the opportunity to practice and calculate data. Each real element has its own identity and using certain information, a person can calculate the atomic mass