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Welcome to the CHEM 119 SI Session For Dr. Altemose

Howdy! Please be sure to:

  1. Scan the QR code
  2. Don’t be afraid to ask questions! There is no such thing as a dumb question!
  3. Participate in activities :D

Topics for Today:

  • Periodic Trends

Next Session: Sunday (9/25) Zoom @ 5-6PM

QR Code

Question of the Session!

Would you rather be forced to go 15 mph under or 15 over the speed limit? You can get tickets for both.

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Warm-Up (5 mins)

  1. As you go across a period, atomic size ______ (increases or decreases) and effective nuclear charge ______ (increases or decreases).

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  • What is ionization energy?

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  • Why is it easier to remove an electron from Cs than Li?

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  • What is electron affinity?

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Directions: Work in pairs to answer the following questions.

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Main Activity (20 mins)

  1. Order the following elements from smallest to biggest:

As, P, Sb, Mc, N

  • Order the following elements from lowest to highest effective nuclear charge:

Br, F, I, At, Ts, Cl

  • Order the following elements from lowest to highest ionization energy:

Sg, Cr, Mo, W, Pr

  • Order the following elements from lowest to highest electron affinity:

Rb, Pd, Mo, Xe, I

Directions: Work on the following problems in groups of 3-4.

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Cool Down (5 mins.)

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  1. Which of the following is incorrectly ordered from lowest to highest electron affinity?
    1. Li < B < C < O < F
    2. Cs < Rb < Na < Li
    3. Zr < Nb < Rh < Pd,
    4. Si < Mg < S < Cl

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Directions: Work on the following problems in groups of 3-4.