In exactly 1 mol Hg₂(NO₃)₂ , there are 2 mol Hg, 2 mol N and 6 mol O.
Since the molecular formula of Hg₂(NO₃)₂ shows that for every mole of the substance, we have 2 moles of Hg, 2 moles of N and 6 moles of O.
So, in exactly 1 mol Hg₂(NO₃)₂ , there are 2 mol Hg, 2 mol N and 6 mol O.
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Lithium's atomic weight is 6.94 g/mol.

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<span>2 HCl + Ba(OH)2 = BaCl2 + 2 H2O is the answer.</span>
Answer:
A
Explanation:
Sodium has 11 electrons and Magnesium has 12 electrons. Since here you need to consider atoms, they must have equal amount of protons as electrons to be considered neutral, and so an atom.
So simply 11+12 =23