+2 is the oxidation number for Zinc
<span>Oxidation Number for a Transition metal = Number of Unpaired d-electrons + Two s-electrons
</span>[Ar]4s2 3d10 is the electron configuration for zinc. The d-block is full with 10 electrons meaning there are no unpaired d-electrons, so the oxidation number is 0 unpaired d-electrons + 2 s-electrons = +2
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Answer:
Mg(NO4)2 is 180.3 g/mol
Explanation:
First find the substance formula.
Magnesium Nitrate.
Magnesium is a +2 charge.
Nitrate is a -1 charge.
So to balance the chemical formula,
We need 1 magnesium atom for every nitrate atom.
2(1) + 1(-2) = 0
So the substance formula is Mg(NO4)2.
Now find the molar mass of Mg(NO4)2.
Mg = 24.3 amu
N = 14.0 amu
O = 16.0 amu
They are three nitrogen and twelve oxygen atoms.
So you do this: 24.3 + 14.0(2) + 16.0(8) = 180.3 g/mol
So the molar is mass is 180.3 g/mol.
The final answer is Mg(NO4)2 is 180.3 g/mol
Hope it helped!