Answer: The ion formed after the reduction of bromine is 
Explanation:
The electronic configuration of Sodium (Na) = ![[Ne]3s^1](https://tex.z-dn.net/?f=%5BNe%5D3s%5E1)
The electronic configuration of Bromine (Br) = ![[Ar]3d^{10}4s^24p^5](https://tex.z-dn.net/?f=%5BAr%5D3d%5E%7B10%7D4s%5E24p%5E5)
From the above configurations, Sodium ion will loose 1 electron in order to gain stable electronic configuration and that electron is accepted by the Bromine atom because it is 1 electron short of the stable electronic configuration.
(oxidation reaction)
(Reduction reaction)
Bromine atom is reduced to form 
Reduction reactions are the reactions in which the element gain electrons.
Oxidation reactions are the reactions in which the element looses its electrons.
It would be 3C + 4H2 -> C3H8
She will most likely observe that the temperature
does not change during melting because the heat absorbed is used to overcome
intermolecular forces rather than to increase the kinetic energy of the
particles if she measures the temperature of the water in the beaker.
Answer:
Yield of reaction is 76.7%
Explanation:
The reaction of salicylic acid with acetic anhydride to produce acetyl salicylic acid is 1:1. That means 1 mole of salicylic acid reacts with 1 mole of acetic anhydride (Acid is catalyst of reaction).
Moles of salicylic acid are:

And moles of acetic anhydride are:

As salicylic acid is limiting reactant, theoretical moles of acetyl salicylic acid are 0.04127mol. That means theoretical mass of acetyl salicylic acid is:

Thus, yield of reaction is:
<em>76.7%</em>