The document discusses several chemistry concepts: 1) It asks to identify the element represented by the electron configuration 1s2 2s2 2p6 3s2 3p4 (calcium), its group and period. 2) It asks for the quantum numbers of the element calcium-20. 3) It asks to determine the molecular structure of SO2 using VSEPR theory (trigonal bent). 4) It asks to determine the molecular structure of CCl4 using hybridization theory (tetrahedral). 5) It asks which compounds are included in the category of van der Waals bonds (HCl, HBr, HI).

1. Soal kimia
1. We have = 1s2 2s2 2p6 3s2 3p4 , determine :
(diketahui= 1s2 2s2 2p6 3s2 3p4,tentukan :
a. nomor atom unsur netralnya
(the number atom of netral element)
b. terletak pada golongan
(the position on group)
c. terletak pada periode.
(the position on period)
2. Bilangan kuantum 20Ca adalah...
(the quantum number of 20Ca is)
3. Tentukan Bentuk molekul SO2, berdasarkan teory VSEPR
(determine the types of molecules of the compound SO2,based on VSEPR theory !
4. Tentukan bentuk molekul CCl4 ,berdasarkan teori hibridisasi.
5. Apakah rumus molekul yang termasuk ke dalam ikatan van der waals (What are the
compounds included in the van der waals bond?)
Nama : Risyanti
Kelas : XI IPA 1

2. Solution :
1. a. 1s2 2s2 2p6 3s2 3p4 = 16
b. 3s2 3p4 = 2 + 4 = group 6
c. 3s2 3p4 = period 3
2. 20Ca (Ar18) 4s2
4s2 n = 4 , l = 0 , m = 0 , s = -
1
2
3. SO2
S = group VI A Valence electrons 6
O = group VI A Valence electrons 6
PEI (X) = 2
PEB (E) = 1
PET = 3
AX2E
( Trigonal bentuk V )
xx
X
x
X
xS
+

3. 4. CCl4
C =1s2 2s2 2p2
4Cl- = (Ne10) 3s2 3p5
____ ___ ___ ___
2s2
2p2
___ ___ ___ ___
4Cl-
5. The solution are :
HCl,HBr,HI