menentukan periode dan unsur golongan

<p><strong>Pembahasan</strong>&nbsp;</p><p>Gunakan aturan Aufbau untuk pengisian elektron2 pd orbitalnya</p><p><i>Perhatikan yg ditebalkan pd konfigurasi elektron tsb, yg merupakan elektron terluar (eletron valensi) untuk menentukan golongan dan periode unsur yg dimaksud</i></p><p>&nbsp;</p><p><i>a. </i>X₃₀ : &nbsp;1s2 &nbsp;2s2 2p6 &nbsp;3s2 3p6 &nbsp;<strong>4s2 3d10</strong></p><p>Golongan <strong>IIB &nbsp;</strong>periode <strong>4</strong></p><p>&nbsp;</p><p><i>b. </i>Z₂₀: 1s2 &nbsp;2s2 &nbsp;2p6 &nbsp;3s2 3p6 <strong>4s2</strong></p><p>Golongan ⁠⁠⁠⁠⁠⁠⁠<strong>IIA &nbsp;</strong>periode <strong>4</strong></p><p>&nbsp;</p><p><i>c. </i>A₁₀: 1s2 &nbsp;<strong>2s2 2p6</strong></p><p>Golongan <strong>VIIIA </strong>periode <strong>2</strong></p><p>&nbsp;</p><p><i>d. </i>D₆₀:&nbsp;</p><p>2 &nbsp; &nbsp; 1s2 &nbsp;</p><p>8 &nbsp; &nbsp; 2s2 2p6 &nbsp;</p><p>18 &nbsp; 3s2 3p6 3d10 &nbsp;</p><p>22 &nbsp; 4s2 4p6 4d10 &nbsp;<strong>4f4</strong></p><p>&nbsp;8 &nbsp; &nbsp;5s2 &nbsp;5p6&nbsp;</p><p>&nbsp;2 &nbsp; &nbsp;<strong>6s2</strong></p><p>Golongan ⁠⁠⁠⁠⁠⁠⁠<strong>VIB </strong>periode <strong>6</strong></p><p>&nbsp;</p>