Ca2 ; Z=20
1s² 2s² 2p⁶ 3s² 3p⁶ 4s²
The electron configuration for a Ca2+ cation is 1s²2s²2p63s²3p6, which reflects the removal of the two valence electrons from the 4s orbital, resulting in a configuration isoelectronic with argon.
The electron configuration of neutral calcium (Ca) is 1s²2s²2p63s²3p64s². When forming a Ca2+ cation, calcium loses both of its valence electrons from the 4s orbital. Therefore, the electron configuration for a Ca2+ cation becomes 1s²2s²2p63s²3p6, which is isoelectronic with the noble gas argon (Ar). This reflects that Ca2+ has achieved a stable noble gas electron configuration by shedding the two electrons from its outermost shell.
The electron configuration of C a 2 + is simply [ A r ] , which indicates that it has achieved a stable noble gas configuration by losing two electrons from the neutral calcium configuration. This reflects the loss of the outermost electrons that are found in the 4 s orbital. The resulting configuration shows that C a 2 + now has the same electron configuration as argon.
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Penjelasan dengan langkah-langkah:hari 1 = 100 like (dah diberi)now kita cari dari hari 2 sampai hari 7---hari 2: 80% lebih sedikit dari hari 1= 100 - 80% dari 100= 100 - 80= 20 like---hari 3: 50% lebih sedikit dari hari 2= 20 - 50% dari 20= 20 - 10= 10 like---hari 4: 150% lebih banyak dari hari 3= 10 + (150% dari 10)= 10 + 15= 25 like---hari 5: 50% lebih sedikit dari hari 4= 25 - 50% dari 25= 25 - 12.5= 12.5 like---hari 6: 25% lebih sedikit dari hari 3= 10 - 25% dari 10= 10 - 2.5= 7.5 like---hari 7: sama dengan hari 4= 25 like---so now jodohkan like dgn hari² yg ditanya tu yajumlah like hari ketiga: 10jumlah like hari keenam: 7.5jumlah like hari ketujuh: 25