8. Here's another calorimetry problem to solve: A solid s cs ubstance with a mass of ty 200g is at its melting point temperature in a calorimeter. While the substance changes from a solid to a liquid at the same
temperature, the 400g mass of water in the calorimeter goes from an initial temperature of 80°C to a
final temperature of 30°C. (a) How much heat did the water lose while the substance melted? (b)
What is the heat of fusion of the substance that melted?
Your response here.

i know this one but can't get it

Explanation:

"among the transition metal elements, manganese and zinc have a slight lowering of electronegativities. the reason behind this is that the nuclear charges of these elements are slightly weaker than the other transition metal elements due to the way their valence electrons are filled up. both manganese and zinc have their valence electrons filled up to the 4th shell with 1 pair of electrons (4s2) completely occupying it. although the electrons in the 3rd shell (3d) are yet to be paired since the outer most shell is filled up, the ability of the nucleus to attract electrons is lessened. hence,   the electronegativity (or the ability to attract electrons) is lessened."