The amout of heat needed to change the temperature of water can be calculated as
where "{m_{{H_2}O}} = \\rho V" - the mass of water and "c" is the specific heat of water. Now let's fint "Q"
(we use that "V = 85.0[{\\rm{c}}{{\\rm{m}}^3}] = 85.0 \\cdot {10^{ - 6}}[{{\\rm{m}}^3}]" and "c = 4.18[\\frac{{\\rm{J}}}{{{\\rm{g}} \\cdot {\\rm{^\\circ C}}}}] = 4180[\\frac{{\\rm{J}}}{{{\\rm{kg}} \\cdot {\\rm{^\\circ C}}}}]" )
Next we can find the number of moles in "5.17[{\\rm{g}}]" grams of "CaC{l_2}" . Calculate the molar mass of "CaC{l_2}"
"{M_{CaC{l_2}}} = {M_{Ca}} + 2{M_{Cl}} = 40.08[\\frac{{\\rm{g}}}{{{\\rm{mol}}}}] + 2 \\cdot 35.45[\\frac{{\\rm{g}}}{{{\\rm{mol}}}}] = 110.98[\\frac{{\\rm{g}}}{{{\\rm{mol}}}}]"(atomic weights of atoms can be found in the periodic table). Thus the number of moles is
and the molar heat of solution is
(!!!)Note: please check the initial conditions of the problem - they can be wrong because the real value is "{C_\\nu } \\approx 83000[\\frac{{\\rm{J}}}{{{\\rm{mol}}}}]" )
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