Lecture Note
1 8 1 1 8 1 8 18 18 2 8 2 8 2 18 8 2 8 Traits Periodic Element Some of the periodic properties that will be discussed here are radius atom, energy ionization, electronegativity, affinity electron, characteristic metal, And point melt as well as point boiling. a. Fingers Atom Fingers atom is distance from core atom until skin outermost. For for elements in the same group, the atomic radius decreases as the number goes down large because the number of shells an atom has increases, so skin outermost increasingly Far from core atom. 11 Na 19 K 37 Rb 55 Cs Picture 1. Fingers atoms of elements in One group, from on to lower increasingly big. Elements Which a period own amount skin Which The same. Will but, no means they own fingers atom Which The same also. The more to right location element, proton And electron Which owned increasingly Lots, so that tug core with electron increasingly strong. As a result, the outer electrons are pulled closer towards the nucleus. So, for elements in the same period, the atomic radius increases to the right increasingly small. 19 K 20 Ca 31 Ga 35 Br Picture 2. Fingers atom elements in one period, from left to right increasingly small In One group, configuration elements One group have amount electron valence The same And amount skin increase. As a result, the distance between the valence electrons and the nucleus increases, so that fingers atom in One group increasingly to lower increasingly big . So can concluded: 1) In One group, fingers atom increase big from on to lower. 2) In One period, fingers atom increasingly small from left to right. 1 2 3 7 8 8 18 18 2 8 2 8 2 8 2 8
a. Ionization Energy Ionization energy is the energy required to release electron outermost something atom. Energy ionization This stated in unit kJ mol –1 . Elements Which group, energy ionization increasingly to lower gets smaller because the outermost electrons are farther from the nucleus (attractive force core increasingly weak), so that electron outermost increasingly easy released. Meanwhile, for elements in the same period, the attraction of the core increases right increasingly strong, so that energy ionization on generally increasingly to right increasingly big. There is a number of exception Which need noticed. Group IIA, VA, And VIIIA it turns out have energy ionization Which very big, even more big than energy ionization element in adjacent right, namely IIIA and VIA. This happens because the elements of group IIA, VA, and VIIIA have relatively stable electron configurations, so that electron hard released. 2,500 2,000 1,500 1000 500 0 10 18 36 54 86 Number Atom Picture 3. Connection energy ionization with number atom. He Periode 2 Periode 3 Ne Periode 4 Periode 5 Periode 6 F Ar N Kr H O Cl Xe Rn Be C P I S B Mg Si As As Ge Ga Te Sb Po Pb Al Ca Sn Sr In Tl Bi Li Na Ga Ba Cs Lu Ra K Rb En er g i Io n isas i (k J m o l –1 )
IA 1 H 2,1 3 Li 1,0 11 Na VIIIA 2 He IIA 4 Be 1,5 12 Mg IIIA IVA VIA VIIA VIIIB 5 B 2,0 13 Al 6 C 2,5 14 Sl VA 7 N 3,0 15 P 8 O 3,5 16 S 9 F 4,0 17 Cl – 10 Ne – 18 Ar c. Electronegativity Electronegativity is the ability or tendency of a atom For catch or interesting electron from atom other. For example, fluorine has a tendency to attract electrons more strongly than hydrogen. So, can concluded that electronegativity fluorine more big than hydrogen. Draft electronegativity This First time submitted by Linus Pauling (1901 – 1994) on year 1932. Elements Which group, electronegativity increasingly to lower increasingly small because style pull core increasingly weak. Whereas elements Which a period, electronegativity increasingly to right increasingly big . Will but need remembered that group VIIIA No have electronegativity. This is because it already has 8 electrons in its shell outermost. So electronegativity biggest is at on group VIIA. Mark Electronegativity Elements 0.9 1,2 IIIB IVB VB VIB VIIB IB IIB 1.5 1.8 2.1 2.5 3.0 – 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 K Ca Sc Ti V Cr MnFe _ Co Ni CuHZn _ No Ge US Se Br Cr 0.8 1.01 1.3 1.5 1.6 1.6 1.5 1.8 1.8 1.8 1.9 1.6 1.6 1.8 2.0 2,4 2.8 – 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 Rb Sr Y Zr Nb Mo Tc Ru Rh Pd Ag Cd In Sn SB Te I Xe 0.8 1.0 1,2 1.4 1.6 1.8 1.9 2.2 2,2 2,2 1.9 1.7 1.7 1.8 1.9 2.1 2.5 – 55 56 57 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 Cs Ba La Hf Ta W Re Os Ir Pt Au Hg Tel PB Ms Po At Rn 0.7 0.9 1.1 1.3 1.5 1.7 1.9 2.2 2,2 2,2 2.4 1.9 1.8 1.8 1.9 2.0 2,2 – 87 Fr 0.7 88 Ra 0.9 89 Air conditioning 1.1 d. Affinity Electron Affinity electron is energy Which join process addition 1electron on One atom neutral in form gas, so that formed ion charged –1 . Affinity electron Also stated in kJ mol –1 . Element Which own affinity electron marked negative, means have trend more big in absorb electron than element Which affinity the electron marked positive. More and more negative mark affinity electron, so increasingly big trend element the in absorb electron (trend form ion negative). From characteristic This can concluded that: 1) Within a group, the electron affinity tends to decrease from on to lower. 2) In one period, the electron affinity tends to increase from left to right. 3) Except for alkaline earth elements and noble gases, all group elements main have affinity electron marked negative. Affinity electron biggest owned by group halogen. Affinity elektron Elements on Group Main Group Period HE IIA IIIA IVA VA VIA VIIA VIIIA 1 H –73 He's 21 2 Li –60 Be 240 B –27 C –122 N 0 O –141 F –328 Ne 29
3 Na –53 Mg 230 Al –44 Si –134 P –72 S –200 Cl –349 Ar 35 4 K –48 Ca 156 No –30 Ge –120 US –77 Se –195 Br –325 Cr 39 5 Rb –47 Sr 168 In –30 Sn –121 SB –101 Te –190 I –295 Xe 41 6 Cs –30 Ba 52 Tel –30 PB –110 Ms –110 Po –180 At –270 Rn 41 e. Characteristic Metal By chemistry, characteristic metal linked with electronegativity, that is trend let go electron form ion positive. So, characteristic metal depends on energy ionization. Reviewed from configuration electron, element- element metal tend release electron (own energy ionization Which small), whereas elements No metal tend catch electron (own electronegativity Which big). According to the trend of ionization energy and electron gatifan, so characteristic metal-nonmetal in periodic element is: 1) From left to right in one period, the metallic properties decrease, whereas characteristic nonmetal increase. 2) From top to bottom in a group, metallic properties increase, whereas characteristic nonmetal reduce. So, the metal elements are located at the bottom-left part of the system periodic element, whereas elements nonmetal located on part top right. The boundaries between metals and nonmetals in the periodic system are frequent depicted with ladder diagonal striped thick , so that element- elements around the border area between metals and nonmetals has both metallic and non-metallic properties. those elements called element metalloids . For example is boron And silicone. Besides That, characteristic metal Also relate with reactivity something element. Reactive It means easy react. Elements metal on system periodic element increasingly to lower the more reactive (more easy react) Because the more easy release electron. On the contrary, elements No metal on system periodic increasingly to lower increasingly not enough reactive (more hard react) Because the more hard catch electron. So, The most reactive metal elements are group IA (alkali metals) And element nonmetal Which most reactive is group VIIA (halogen) . f. Point Melt And Point Boiling Based on the melting point and boiling point it can be concluded as following. 1) In One period, point liquid And point boiling go on from left to right until group IVA, then drops drastically. Liquid point and point boiling Lowest owned by element group VIIIA. 2) In One group, it turns out There is two type trend: element- element group HE – IVA, point liquid And point boiling increasingly low from top to bottom; elements of groups VA – VIIIA, melting point and point he boiled increasingly tall.
Traits Periodic Element
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