Answer: Nucleus of an atom is heavy and positively charged because nucleus is only made up of protons and neutrons.
The formal charge on each atom can be known by counting up the number of valence electrons that is present on each atom.
<h3>What is Lewis structure?</h3>
The term Lewis structure is the representation of a compound using its symbols and showing the valence electrons as dots. This question is incomplete as the Lewis structures were not shown.
If it is shown, we can know the formal charge on each atom by counting up the number of valence electrons that is present on each atom.
Learn more about Lewis structure: brainly.com/question/4144781
D is the only choice here that is appropriate given neutrons' lack of charge
ΔHrxn = ΣδΗ(bond breaking) - ΣδΗ(bond making)
Bond enthalpies,
N ≡ N ⇒ 945 kJ mol⁻¹
N - Cl ⇒ 192 kJ mol⁻¹
Cl - Cl⇒ 242 kJ mol⁻¹
According to the balanced equation,
ΣδΗ(bond breaking) = N ≡ N x 1 + Cl - Cl x 3
= 945 + 3(242)
= 1671 kJ mol⁻¹
ΣδΗ(bond making) = N - Cl x 3 x 2
= 192 x 6
= 1152 kJ mol⁻¹
δHrxn = ΣδΗ(bond breaking) - ΣδΗ(bond making)
= 1671 kJ mol⁻¹ - 1152 kJ mol⁻¹
= 519 kJ mol⁻¹
