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Calculate the heat of crystallization of 10 grams of sodium acetate trihydrate (NaC2H3O2•3H2O) when it is cooled from 50°C to 10°C and crystallizes. The specific heat capacity of water is 4.18 J/g°C. The molar mass of sodium acetate is 82.03 g/mol.

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To calculate the heat of crystallization, we first need to determine the amount of heat released when the sodium acetate trihydrate is cooled from 50C to 10C. The molar mass of sodium acetate trihydrate is the sum of the molar mass of sodium acetate  82.03 g/mol  and three times the molar mass of water  3 * 18.015 g/mol . Molar mass of sodium acetate trihydrate = 82.03 + 3 * 18.015 = 82.03 + 54.045 = 136.075 g/molNow, we need to find the moles of sodium acetate trihydrate in the 10 grams sample.moles = mass / molar mass = 10 g / 136.075 g/mol = 0.0735 molNext, we need to calculate the heat released when the sodium acetate trihydrate is cooled from 50C to 10C. We will use the specific heat capacity of water  4.18 J/gC  as an approximation for the specific heat capacity of the sodium acetate trihydrate solution.T = T_final - T_initial = 10C - 50C = -40Cq = mcTwhere q is the heat released, m is the mass of the sample  10 g , c is the specific heat capacity  4.18 J/gC , and T is the change in temperature  -40C .q =  10 g  4.18 J/gC  -40C  = -1672 JSince the heat released is negative, it means that the sodium acetate trihydrate is losing heat as it cools down.Now, we can calculate the heat of crystallization per mole of sodium acetate trihydrate.Heat of crystallization = q / moles = -1672 J / 0.0735 mol = -22754 J/molThe heat of crystallization of sodium acetate trihydrate when it is cooled from 50C to 10C and crystallizes is approximately -22,754 J/mol.

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