When 21.45 g of kno3 was dissolved in water in a calorimeter, the temperature fell from 25.00°c to 14.14 °c. if the heat capacity is 0.505kj/°c, what will be the delta h for the solution process.

25.9 kJ/mol. (3 sig. fig. as in the heat capacity.)

The process:

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How many moles of this process?

Relative atomic mass from a modern periodic table:

Molar mass of :

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Number of moles of the process = Number of moles of dissolved:

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What's the enthalpy change of this process?

for . By convention, the enthalpy change measures the energy change for each mole of a process.

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The heat capacity is the least accurate number in these calculation. It comes with three significant figures. As a result, round the final result to three significant figures. However, make sure you keep at least one additional figure to minimize the risk of rounding errors during the calculation.