An element with 8 valence electrons is Neon (Ne).
Ps: Any element under group 18 has 8 valence electrons except for Helium (He).
If you look at AIF3 and AICI3, the F ion is smaller than a CI ion. that’s why AICI3 will make a covalent bond while AIF3 will make a ionic bond. explanation: AICI3 doesn’t have a complete transfer of electrons between the metal and the non-metal.
Answer:
a. Zinc is the limiting reactant.
b. 
c. 
Explanation:
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a. In this case, when zinc metal reacts with bromine, the following chemical reaction takes place:

Thus, since zinc and bromine react in a 1:1 mole ratio, we can compute their reacting moles to identify the limiting reactant:

Thus, since zinc has the fewest moles we infer it is the limiting reactant.
b. Here, we compute the grams of zinc bromide via both reactants:

That is why zinc is the limiting reactant, as it yields the fewest moles of zinc bromide product.
c. Here, since just 0.722 mol of bromine would react, we compute the corresponding mass:

Thus, the leftover of bromine is:

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