The specific heat of water and steam (water vapor) are 4.18 J/gºC and 2.10 J/gºC respectively. Heating a 74.0 g sample of
water from 88.3 °C to water vapor at 112.5 °C requires 172.58 kJ
of heat. Calculate the heat of vaporization of water in kJ/g.
Assume the boiling point of water is 100 °C.

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"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."