2 Alkali metals Highly reactive metals in group 1A of the periodic table Alkaline earth metals Fairly reactive metals in group 2A of the periodic tableTransition metals Those elements found in the d block of the periodic table whose properties tend to be less predictable based simply on their position in the table
3 Halogens families Highly reactive nonmetals in group 7A of the periodic table Noble gases The group 8A elements, which are largely unreactive (inert) due to their stable filled p orbitals
5 Atomic radii A measure of the size of an atom Ionic radii A measure of the size of an atoms ion in a crystal lattice formElectronegativity The ability of an atom to attract electrons to itselfIonization energy The energy required to remove an electron from an atom or ion in its gaseous state
6 Knowing the Periodic Table Rows are referred to as periodsColumns are referred to as families or groupsElements within a group generally have similar propertiesWhen elements are arranged in order of increasing atomic number, there are recurring physical and chemical properties Periodic law
8 Development of the Periodic Table The number of known elements drastically increased in the early 1800sIn 1869, Dmitri Mendeleev from Russia and Lothar Meyer form Germany published classification systemsMendeleev is given credit for organizing elements into the periodic table
9 Development Cont.The periodic table is an arrangement of elements in which they are separated into groups based on repeating propertiesMendeleev arranged the elements in order of increasing mass (there were some exceptions Ex. Te and I)It was later realized that arranging by properties, rather than mass was more accurateMendeleev left gaps for undiscovered elements, but accurately predicted their properties
10 Modern Periodic TableIn the early 1900’s Henry Moseley determine atomic numbers of each known elementThe modern table is arranged based on increasing atomic numbersEach period on the periodic table corresponds to a principal energy levelElements with similar chemical and physical properties end up in the same columnDo periodic Table Worksheet with this Info.
11 Main Chemical Families Alkali MetalsAlkaline Earth MetalsTransition MetalsHalogensNoble gases
12 Properties of Alkali Metals (Group 1) Have metallic properties of metalsShiny luster, malleability, high thermal and electrical conductivitySoft solids at room temperature, low melting points and densitiesVery reactive! (Especially with water)Found as compounds in nature, never as free elementsLose an electron when they react, thus have a +1 oxidation state
13 Properties of Alkaline Earth Metals (Group 2) Soft metalsVery reactive! (Less reactive than alkali metals)All except beryllium (Be) react with waterMost occur naturally only in compoundsWhen reacted, they give up 2 electrons and have a +2 oxidation state
14 Properties of Transition Metals (Groups 3-12) Most transition metals have common metallic characteristics with other elements in their families ; except zinc (Zn), cadmium (Cd), and mercury (Hg)Can exist in several common oxidation statesAre likely to form complexes with unbalanced charges and excessive electrons
15 Properties of Halogens (Group 17) All halogens are nonmetalsGenerally poor conductors of heat and electricityAre not all found in the same state of matterThe only family with all 3 states of matterAt room temperature, fluorine (F) and chlorine (Cl) are gases. Bromine (Br) is a liquid. Iodine (I) and astatine (At) are solids.Very reactive (will even react with glass!)Halogens are commonly found as diatomic molecules (F2, Cl2)Gain an electron when reacted; oxidation state of -12nd 6th
16 Properties of Noble Gases All gases at room temperatureOdorless and colorlessVery low reactivityExist as unbound elements in natureReferred to as inert (nonreactive)Make graphic organizers of this information4th 7th
17 Trends of Atomic Radii Size of atoms is expressed as the atomic radius Atomic radii generally decrease from left to right across a period and increase from top to bottom of a groupPrincipal quantum number (n) of outer-level electrons increases by one from period to periodEx. Elements in period 1, n=1. For period 2, n=2, and so onAs n increases down a family, the average position of outer- level electrons is farther from the nucleusAs a result, atoms are LARGER
18 Trends of Ionic Radii Ion atom or group of atoms with a charge Cation atoms that have lost 1 or more e- and have a + chargeCations are smaller in radius because they have lost e-Ex. Ca2+ is smaller than Ca because it has lost 2 e-Anion atoms that have gained 1 or more e-Anions are larger because they have gained e-Ex. Br- is larger than Br because it has one more e- orbitingTrends of anions and cations are similar to that of their neutral atomic radii
19 Electronegativity Trend Number of protons and the principal quantum number influence electronegativityGenerally, electronegativity increases from left to right across a period (because the # of p+ increases)It generally decreases from top to bottom of a group (due to outer energy level e- being farther from the nucleus
20 Ionization Energy Trend In the event of multiple e- being removed from an atom, there are different ionization energies corresponding to each e- removedThe energy required to remove the first e- is referred to as the “first ionization energy”Generally, ionization energy increases from left to right across a period and decreases from top to bottom within a family
21 Ionization Energy Cont. Depends on the force of attraction the nucleus exerts on the e-Also depends on # of p+ and distance of e- from the nucleusThe more p+ force, the more difficult to remove an e-
22 Atomic Radii PracticeArrange the following elements in order of increasing atomic radiiSodiumIronPotassiumSulfurPhosphorusS, P, Fe, Na, K
23 Ionic Radii PracticeArrange the following ion in decreasing order of ionic radiiMg2+F-Cu2+Li+O-Li, Mg, Cu, O, F
24 Electronegativity Practice Which of the following atoms is more electronegative? Which is less?CalciumChlorineExplain why you chose ___ as more electronegative than ___.
25 Ionizing Energy Practice Do metals or non-metals have a higher ionizing energy?List the following elements in order of increasing ionizing energyAuCoPdCo, Pd, Au
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