Periodic PropertiesPeriodic Properties

An Activity in GraphingAn Activity in Graphing

Graphing Periodic PropertiesGraphing Periodic Properties

In this activity you will look at how an In this activity you will look at how an increase in atomic numberincrease in atomic number affects affects the the size size of an atom of an atom (atomic radius)(atomic radius) by graphing experimental data. by graphing experimental data.

ProblemProblem - …? - …?

……How does How does atomic numberatomic number affect affect atomic radiusatomic radius??

HypothesisHypothesis

Increasing the number of particles (pIncreasing the number of particles (p++ e e-- n n00 ) ) in an atom will…in an atom will…

Write down your hypothesis before Write down your hypothesis before beginning!!!beginning!!!

Please return the data tables when you Please return the data tables when you are finished!!!are finished!!!

Variables?Variables?

How does How does atomic numberatomic number affect affect atomic atomic radiusradius??

Independent variable Independent variable Atomic numberAtomic number

Dependent variable Dependent variable Atomic radiusAtomic radius

ProcedureProcedure

1. Obtain a piece of graph paper and place the 1. Obtain a piece of graph paper and place the x-axis along the longest side of the paper.x-axis along the longest side of the paper.

2. Construct a graph with the 2. Construct a graph with the Atomic NumberAtomic Number as as the the independent variableindependent variable (which axis??) and (which axis??) and the the Atomic RadiusAtomic Radius as the as the dependent variabledependent variable (which axis??). (which axis??).

3. Set up your scale so that the data points are 3. Set up your scale so that the data points are

spread out nicely. Only graph elements #1-20. spread out nicely. Only graph elements #1-20.

4. Use pencil to set up your graph…(you will 4. Use pencil to set up your graph…(you will make mistakes)…make mistakes)…connect the dotsconnect the dots..

5.5. Label the atoms that have a Label the atoms that have a complete complete outermostoutermost energy level with their element energy level with their element symbol and draw symbol and draw vertical red linesvertical red lines through through them dividing the graph into sections.them dividing the graph into sections.

6. Identify the elements with a 6. Identify the elements with a single electronsingle electron in in their outermost energy level and their outermost energy level and label them label them in blue with their symbolsin blue with their symbols..

7. 7. What do these sections you have created in What do these sections you have created in step 5 and 6 represent?step 5 and 6 represent?

ANALYSIS-ANALYSIS-1.1. Describe the relationship between atomic # and atomic Describe the relationship between atomic # and atomic

radius for elements within the radius for elements within the same period (row)same period (row)..

2. Describe the relationship between atomic # and atomic 2. Describe the relationship between atomic # and atomic radius for elements within the radius for elements within the same group (family).same group (family).

3.3. Where do you think the atom with the largest atomic Where do you think the atom with the largest atomic radius would be on the P.T.? The smallest atomic radius would be on the P.T.? The smallest atomic radius? What is the name of the elements?radius? What is the name of the elements?

4.4. Write a conclusion. Remember, your conclusion should Write a conclusion. Remember, your conclusion should answer the problemanswer the problem and be and be supported by datasupported by data..

You will hand in your problem, hypothesis, You will hand in your problem, hypothesis, variables, labeled graph and analysis variables, labeled graph and analysis

http://www.webelements.com/webelementhttp://www.webelements.com/webelements/properties/text/image-flash/covalent-radis/properties/text/image-flash/covalent-radius.htmlus.html