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Ionization Energies and Ions. Trends in Ionization energy. The amount of energy required to completely remove an electron from a gaseous atom. Removing an electron makes a +1 ion. The energy required to remove the first electron is called the 1 st ionization energy.
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Trends in Ionization energy • The amount of energy required to completely remove an electron from a gaseous atom. • Removing an electron makes a +1 ion. • The energy required to remove the first electron is called the 1stionization energy.
Trends in Ionization energy • The2ndionization energy is the energy required to remove the second electron(s). • The 3rdIE is the energy required to remove a third electron.
First Ionization Energy • The first electron is pulled off of the atom becoming a +1 ion. • As a result, this magnisium’s atomic radius expands. Mg Mg +
Second Ionization energy • The second electron is pulled off of the +1 ion creating a +2 ion, requiring more energy than the 1st ionization energy. • As a result, the outermost electron shell of this magnisium ion goes away. Fat and Happy Octet Rule Like a Noble Gas! Mg 2+ Mg
Third Ionization Energy • The 3rd ionization energy requires more energy than the 1st and 2nd IE…a lot more! • As a result the ion expands, acquiring a +3 charge. 3+ Mg Mg
First Ionization Energies Noble Gases Alkali Metals
IONS • IONSare atoms or groups of atoms with a positive or negative charge. • Taking away an electron from an atom gives a CATION with a positive charge This a Cat-ion… He’s a “PLUSSY CAT”
IONS • Adding an electron to an atom gives an ANION with a negative charge. “Ann Ion is always so NEGATIVE!”
IONS • To tell the difference between an atom and an ion, look to see if there is a charge in the superscript! Examples: Na+ Ca+2I - O-2 Ions Na Ca I O Elements
Forming Cations & Anions An ANION forms when an atom gains one or more electrons A CATION forms when an atom loses one or more electrons. F + e- F- Mg Mg2+ + 2 e-
PREDICTING ION CHARGES In general • metals (Mg) lose electrons ---> cations • nonmetals (F) gain electrons ---> anions “Givers” “Takers”
Learning Check – Counting State the number of protons, neutrons, and electrons in each of these ions. 39 K+16O -241Ca +2 19 8 20 #p+ ______ ______ _______ #no ______ ______ _______ #e- ______ ______ _______ 8 19 20 20 8 21 18 18 10
One More Learning Check Write the nuclear symbol for the following ions: A. 9 p+, 10 n, 10 e- ___________ B. 17p+, 18n, 18e- ___________ C. 12p+, 12 n, 10 e- ___________ - F - Cl 2+ Mg
-3 -2 -1 +1 +2 Charges on Common Ions By losing or gaining e-, atom has same number of e-’s as nearest Group 8A atom.
One Last Check • Identify the following charges for the following ions: • Na __________ • O __________ • F __________ • Mg __________ • N __________ • Ba __________ • Cl __________ Na+ O 2- F- Mg 2+ N 3- Ba2+ Cl-
Explain Yourself! Compare and contrast an ion with a positive charge to one with a negative charge.
Givers and Takers • You each have an element. • Identify if your element is a giver or a taker of electrons • Identify how many electrons your element can • give or take to become an ION. • You may give or take with more than on other element, as long as you fulfill the needs of all elements you connect or BOND with.
Closing Time… • Pick any element and describe how many ionization energies it must go through to achieve a “fat and happy” octet rule. • Describe what will happen in regards to the atomic radius as your element goes through the different ionization energies.