Before Bell Rings Grab 3 papers From Side Table Have your Lewis Dot and Electron Configuration WSs out for me to check.

ETD #7 2019 Give the complete Lewis Dot for Nitrogen, Phosphorus, and Arsenic. Why are the masses on the periodic table decimals?

ETD #7 2019 Give the complete Lewis Dot for Nitrogen, Phosphorus, and Arsenic. Why are the masses on the periodic table decimals? The atomic mass on the periodic table is the weighted average mass of the isotopes for that element. All three elements should have 5 dots around their chemical symbol. Remember we don’t count the d block when we are doing Lewis Dots. The numbers on the PT for atomic mass are decimals because it is the weighted average of all the naturally occurring isotopes of that element. This means that we don’t just take the average of the different isotopes, we have to look at prevalent those isotopes are. So if most of the isotopes of a certain element have an atomic mass of 16, the mass on the PT will be closest to 16.

Learning Targets I can describe the trends in atomic radius, ionization energy, and electronegativity on the periodic table.

Coulombic Attraction Attraction between oppositely charged particles Increases as the charges get closer Decreases as they get farther away What are the oppositely charged particles in an atom? Don’t need to memorize this. It is the attraction between oppositely charged particles. This attraction increases as the charges move close together, decreases as the charges move farther away. The oppositely charged particles in an atom are the protons (+ charge) and the electrons (- charge).

Periodic Trends POGIL 3 Roles Facilitator: Keeps group moving C/F Spokesperson: Raises hand, answers ?s A/D Reader: Reads aloud B/E STOP at Stop Signs so I can ask some questions If you get done, start working on Ionization Across the Nation Packet- NOT DUE NEXT CLASS Info on pages 64-65, 346-352

Trends in the POGIL 3 Types of Trends All based on attraction and electron shells Atomic Radius Ionization Energy Electronegativity The trend in atomic radius (the distance from the nucleus to the outermost shell of electrons) is as we move left to right in a row on the periodic table, the AR will decrease. This is because as we move left to right, more protons and electrons are added but the energy level stays the same. This means there is more charge, leading to more attraction. This increased attraction pulls the electron shells in closer to the nucleus, reducing the atomic radius. As we move top to bottom on the PT, the AR increases because as we move down a row, a new electron shell is added to the atom, increasing its radius. Remember the video where the 1s orbital was small, the 2s was bigger, 3s was even bigger,… The trend in ionization energy (the amount of energy required to remove an electron from an atom) is as we move left to right on the PT, the IE will increase. This is because the attraction between the nucleus and the outermost electrons increases, making it more difficult to remove an electron. This means it will require more energy to remove an electron. As we move from top to bottom on the PT, the IE decreases because there is less attraction as the outmost electrons are farther away from the nucleus. This means it will be easier to remove electron and the IE will be lower. The trend in electronegativity ( the measure of the ability of an atom to attract the electrons from another atom when they are covalently bonded) is as we move left to right on the PT, the electronegativity increases until we get to the noble gases. This is because as we move left to right on the PT, the number of protons increase. This means there is more pull from the protons on electrons from other atoms which allows the nucleus to attract the bonded electron more strongly. As we move top to bottom on the PT, the electronegativity decreases. This is because, as we move down the PT, the atoms get larger, making the attractive force of the nucleus weaker, so it will be less electronegative. The noble gases have no electronegativity (at least on the POGIL) because they have a full outer shell and don’t want to gain anymore electrons.

Learning Targets I can describe the trends in atomic radius, ionization energy, and electronegativity on the periodic table.

Homework Periodic Trends POGIL Ionization Across the Nation – Due class after next. Test is planned for Tuesday and Wednesday, 9/31 and 10/1