The atom that would gain two electrons to fill its valence energy level is S(sulfur)
This is because s (sulfur) is in atomic number 16 with 2.8.6 of [Ne] 3s^2 2p^4 electronic configuration. This implies that sulfur has 6 valence electron and therefore it require two electron to fill its valence energy level and obtain 18 rule electrons.
The density of the unknown material is 0.213 ml/g
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Apparent density of the unknown material</h3>
The apparent density of the unknown material is calculated as follows;
Volume of the unknown substance = 126 ml - 102 ml = 24 ml
Density of the unknown substance = mass/volume
Density of the unknown substance = 24 ml / 112.6 g
Density of the unknown substance = 0.213 ml/g
Thus, the density of the unknown material is 0.213 ml/g
Learn more about density here; brainly.com/question/6838128
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