The valence electron configuration for antimony (Sb) is:
Sb = 5s²5p³5d⁰
In SbCl₅²⁻, antimony has a -2 charge i.e. it has 2 additional electrons
Sb²⁻ = 5s²5p⁵5d⁰
Following a two electron transition from p→d orbital we have:
Sb²⁻ = 5s²5p³5d²
There is a total of 5 unpaired electrons (3 in the p and 2 in the d) which can form five bonds with the 5 Cl atoms.
Thus the hybridisation of Sb in SbCl₅²⁻ is sp³d²
Resistance of a material being scratched in known as: Hardness
A carbon iota can bond with four other iotas and is just like the four-hole wheel, whereas an oxygen iota, which can bond only to two, is just like the two-hole wheel.
1) B+3 is ok. The exercise already put B+3. What
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2) Ge is a neutral atom because it doesn't have any charge.
Germanium has 32 electrons and 32 protons because its atomic number is 32.
Be careful with that.
Neutral atoms have the same numbers of electrons and protons.
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3)
