Lecture 6.3- Periodic Trends (Honors)
Upcoming SlideShare
Loading in...5
×
 

Like this? Share it with your network

Share

Lecture 6.3- Periodic Trends (Honors)

on

  • 1,841 views

Section 6.3 lecture for Honors Chem

Section 6.3 lecture for Honors Chem

Statistics

Views

Total Views
1,841
Views on SlideShare
1,838
Embed Views
3

Actions

Likes
1
Downloads
18
Comments
0

1 Embed 3

http://www.slideshare.net 3

Accessibility

Categories

Upload Details

Uploaded via as Microsoft PowerPoint

Usage Rights

© All Rights Reserved

Report content

Flagged as inappropriate Flag as inappropriate
Flag as inappropriate

Select your reason for flagging this presentation as inappropriate.

Cancel
  • Full Name Full Name Comment goes here.
    Are you sure you want to
    Your message goes here
    Processing…
Post Comment
Edit your comment
  • This diagram lists the atomic radii of seven nonmetals. An atomic radius is half the distance between the nuclei of two atoms of the same element when the atoms are joined.
  • The size of atoms tends to decrease from left to right across a period and increase from top to bottom within a group. Predicting If a halogen and an alkali metal are in the same period, which one will have the larger radius?
  • This graph plots atomic radius versus atomic number for 55 elements. INTERPRETING GRAPHS a. Analyzing Data Which alkali metal has an atomic radius of 238 pm? b. Drawing Conclusions Based on the data for alkali metals and noble gases, how does atomic size change within a group? c. Predicting Is an atom of barium, atomic number 56, smaller or larger than an atom of cesium (Cs)?
  • First ionization energy tends to increase from left to right across a period and decrease from top to bottom within a group. Predicting Which element would have the larger first ionization energy—an alkali metal in period 2 or an alkali metal in period 4?

Lecture 6.3- Periodic Trends (Honors) Presentation Transcript

  • 1. Bellwork- Excited? 1s 2 2s 2 2p 6 3s 2 3p 5 4s 2 3d 10 4p 4 What element is this? Does this electron configuration represent an atom in an excited state or in its ground state? Explain.
  • 2. Bellwork- Excited? 1s 2 2s 2 2p 6 3s 2 3p 5 4s 2 3d 10 4p 4 What element is this? As Does this electron configuration represent an atom in an excited state or in its ground state? Explain.
  • 3. Bellwork- Excited? 1s 2 2s 2 2p 6 3s 2 3p 5 4s 2 3d 10 4p 4 What element is this? As Does this electron configuration represent an atom in an excited state or in its ground state? Explain. This As atom is in an excited state; One of the four electrons in the 4p sublevel could relax because a lower energy 3p orbital is unfilled.
  • 4. Lecture 6.3- Periodic Trends
  • 5.
    • The atomic radius measures an atom’s size.
    • It is one half of the distance between the nuclei of two atoms of the same element when the atoms are joined.
  • 6.
      • Group and Periodic Trends in Atomic Size
          • In general, atomic size increases from top to bottom within a group and decreases from left to right across a period.
  • 7.  
  • 8.
    • Across a period left to right
    • Atoms get smaller because there are more protons in the nucleus pulling the electrons in closer.
    • Down a group
    • Atoms get bigger because they have 1 more energy level (layer)
  • 9.  
  • 10. A neutral atom contains an equal number of protons and electrons. When an atom gains or loses electrons it is no longer neutral. It becomes a charged ion. An ion has a charge.
  • 11. If an atom or a compound becomes charged it is called an ion
  • 12. A positive ion is called a cation A negative ion is called an anion Positive + Positive + Positive +
  • 13. Anakin NEGATIVE
  • 14. When an atom gains an electron it gains an additional negative charge. A Chlorine atom will gain one electron to become a Chlorine anion. Cl e - _
  • 15. An Oxygen atom will gain two electrons making an Oxygen ion with a charge of negative two. O e - e - _ 2-
  • 16. Atoms of elements from the left side of the periodic table will lose electrons. When an atom loses an electron it has more protons than electrons, so it is a positively charged ion.
  • 17. Sodium will lose one electron to create a sodium ion with a “plus one” charge Na e - +
  • 18. A Magnesium atom will lose two electrons to form an ion with a charge of positive two. Mg e - + e - 2+
  • 19.
        • The energy required to remove an electron from an atom is called ionization energy .
        • First ionization energy tends to decrease from top to bottom within a group and increase from left to right across a period.
  • 20.  
  • 21.
    • Across a period left to right
    • Atoms get smaller, so it is more difficult to remove tightly held electrons.
    • Down a group
    • Atoms get bigger so outer electrons are easier to remove.
  • 22.
        • Electronegativity is the ability of an atom of an element to attract electrons when the atom is in a compound.
          • Electronegativity values decrease from top to bottom within a group. For representative elements, the values tend to increase from left to right across a period.
  • 23.
    • Explanation of the electronegativity trend is also related to atomic size.
    • The smaller the atom the better it can attract electrons because they are closer to the positive nucleus.