Hey there!:
Molar mass MgCl2 = 95.2110 g/mol
So:
1 mole MgCl2 -------------- 95.2110 g
moles MgCl2 ---------------- 319 g
moles MgCl2 = 319 * 1 / 95.2110
moles MgCl2 = 319 / 95.2110
=> 3.350 moles of MgCl2
Hope that helps!
<span>Answer is: the symbol is Cl.
[Ne ] 3s</span>² 3p⁶ is electric configuration of noble gas argon, neon (Ne) has10 electrons plus 6 electrons in 3s and 3p orbitals. Neutral atom of m<span>onatomic ion that has a charge of 1– has one electron less than argon, so that atom (chlorine) has 17 electrons. Charge of 1- means one electron more for ion: 17 + 1 = 18.
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