VanWyhe SIPC02 AverageAtomicMass.docx - Course: Unit:...

Course: Integrated Physics and Chemistry
Unit: The Structure of Matter
Assignment
:
Average Atomic Mass
Lab Report Expectations and Instructions:
Lab report grades make up 40% of each unit grade. Completing and doing well on projects is very
important for your unit and overall grade.
For this project, you will be using Gizmos simulations through . Please login to
your Gizmos account ( Gizmos Login ) and open the “ Average Atomic Mass ” simulation.
This document will walk you through how to use the Gizmos simulation. Please answer all
questions in the Answer boxes in complete sentences . Leave the rest of the document intact.
Your teacher will include notes in the document and add points in the “Points Earned”
column.
** Please read over the teacher comments after the report is submitted and graded. **
Average Atomic Mass
Student Name: Ella Van Wyhe
Date: 8/16-17/21
Name of Grader: James Haveman
Goals:
 Understand the concept of a weighted average.
 Discover how a mass spectrometer works.
 Calculate the average atomic mass of an element.
 Predict an element’s average mass by examining the relative abundance of its isotopes.
 Predict the most common isotope of an element based on its average atomic mass.
 Explore the concept of mass defect. (Extension)
Vocab:

 Average Atomic
Mass
 Isotope
 Mass Number
 Mass Spectrometer
 Unified Atomic
Mass Unit
 Weighted Average
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Prior Knowledge Question (Do this BEFORE using the Gizmo.)
Question Answer Points
Possibl
e
Points
Earne
d
1. In the image below, the cans of soup
have different masses. Without doing
the math, estimate the average mass
of a can of soup.
I’d estimate the mass to be about
two or three hundred grams.
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2. Now calculate the average mass by
adding up the masses of all the cans
and dividing by the total number of
cans.
What is the average mass of a can of
soup?
The average mass of a can of soup
is 200g.
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3. How close was your prediction? My prediction was almost perfect.
Gizmo Warm-up
Just like cans of soup, atoms of the same element often have
different masses. These different varieties are called isotopes . In
the Average Atomic Mass Gizmo, you will learn how to find the
average mass of an element using an instrument called a mass
spectrometer .
To begin, check that Carbon is selected and the Isotope mix
Custom . Use the sliders to add about 20 atoms each of Carbon-
12 and Carbon-13 to the chamber.
1. In the mass spectrometer, atoms are vaporized (turned into a gas) and ionized (stripped of
electrons). The charged particles are then shot through a tube surrounded by electromagnets. Click
Release atoms and observe the particles as they hit the detector.
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is