History of the Periodic Table

Evaluation/ Assessment Objective Today I will be able to: Analyze patterns to determine the location of mystery elements on the periodic table. Explain the history of the periodic table and how it relates to the nature of discovering scientific knowledge. Evaluation/ Assessment Informal assessment – Listening to group interactions and discussions as they complete the Mendeleev lab of 1869 activity. Monitoring students responses as they complete the periodic table worksheet. Formal Assessment – Analyzing student responses to the exit ticket, periodicity practice and periodic table worksheet Common Core Connection Build Strong Content Knowledge Value Evidence Reason abstractly and quantitatively Make sense of problem and persevere in solving them Model with mathematics Look for and make use of structure Look for and express regularity in repeated reasoning

Lesson Sequence Warm – Up Elaborate: Periodicity Practice Worksheet Informal assessment as students answer questions Formal assessment collecting responses Engage and Explore: The Mendeleev Lab of 1869 activity Informal assessment – monitoring student responses as they arrange the pattern of the elements Explain: History of the Periodic Table Notes Elaborate: Periodic Table Worksheet Evaluate: Exit ticket Formal assessment

Warm - Up Which element has the larger radius? Explain. Be or O Which element has the smaller electronegativity? Explain. Sr or Ra Which element has the greater ionization energy? Explain. S or Cl

Objective Today I will be able to: Analyze patterns to determine the location of mystery elements on the periodic table. Explain the history of the periodic table and how it relates to the nature of discovering scientific knowledge.

Homework Periodic Table Worksheet Study for Periodic Table Exam on Thursday Exam Format – 65 Points 24 multiple choice (1 point each) 10 problems identifying trends (radius, ionization energy and electronegativity – 3 points each) 4 short answer questions about history of the periodic table and oxidation numbers 2-3 points each)

Agenda Warm – Up Periodic Table Exam Study Guide Review Periodicity Worksheet The Mendeleev Lab of 1869 History of the Periodic Table Notes Periodic Table Worksheet Exit Ticket

Review Periodicity Worksheet Volunteers will place answers on the board and discuss correct vs. incorrect answers

The Mendeleev Lab of 1869 Activity Each row will work together Your goal is to construct the periodic table and identify the location of the unknown elements Lay out the arrangement of the known elements first, leave gaps for the missing elements Use the properties on the cards to predict the location of the unknown elements on the periodic table The elements represent the “s” and “p” block only None of the elements repeat

What are the mystery elements? Magnesium (Mg) Fluorine (F) Rubidium (Rb) Krypton (Kr) Sulfur (S) Antimony (Sb) Germanium (Ge)

History of the Periodic Table Notes

Johann Dobereiner (1829) Law of Triads - in triads of elements the middle element has properties that are an average of the other two members when ordered by the atomic weight Example - halogen triad composed of chlorine, bromine, and iodine

John Newlands (1864) Law of Octaves - states that any given element will exhibit analogous behavior to the eighth element following it in the periodic table

Dmitri Mendeleev (1871) Developed the first Periodic Table He arranged his table so that elements in the same column (groups) have similar properties; increasing atomic mass

Dmitri Mendeleev (1871) Broke the trend of arranging elements solely by their atomic mass Wanted to keep elements with similar properties in the same columns Left gaps in his early tables; predicted elements that had not been discovered would fill in those gaps

Dmitri Mendeleev (1871)

Henry Moseley (1913) Found a relationship between an element’s X-ray wavelength and it’s atomic number (number of protons) Periodic Law - when elements are arranged in order of increasing atomic number, their physical and chemical properties show a periodic (repeating) pattern The periodic law is the basis for arranging elements in the periodic table

Glenn Seaborg He reconfigured the periodic table by placing the actinide series below the lanthanide series Awarded a Nobel Prize in 1951 Element 106, Seaborgium (Sg), is named in his honor

Periodic Table Worksheet Use information from notes and textbooks to complete. Upon completion we will review it as a class.

Exit Ticket Write one question that could be used on the exam about one of the periodic trends. (atomic radius, ionization energy and electronegativity). Include the answer to the question