In the laboratory a general chemistry student finds that when 2.84 g of kclo4(s) are dissolved in 107.70 g of water, the temperature of the solution drops from 22.82 to 20.34 °c. the heat capacity of the calorimeter (sometimes referred to as the calorimeter constant) was determined in a separate experiment to be 1.55 j/°c. based on the student's observation, calculate the enthalpy of dissolution of kclo4(s) in kj/mol. assume the specific heat of the solution is equal to the specific heat of water.

Answer : The enthalpy change of dissolution of is 54.3 kJ/mole

Explanation :

Heat released by the reaction = Heat absorbed by the calorimeter + Heat absorbed by the water

where,

q = heat released by the reaction

= heat absorbed by the calorimeter

= heat absorbed by the water

= specific heat of calorimeter =

= specific heat of water =

= mass of water = 107.70 g

= change in temperature =

Now put all the given values in the above formula, we get:

Now we have to calculate the enthalpy change of dissolution of

where,

= enthalpy change = ?

q = heat released = 1.1123 kJ

m = mass of = 2.84 g

Molar mass of = 138.55 g/mol

Therefore, the enthalpy change of dissolution of is 54.3 kJ/mole

answer is a

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."