Lesson: Enthalpy Measurements Glencoe • Chemistry • Matter & Change • Glencoe Science • Chemistry • Matter and Change

Chemistry

In this lesson, we will learn how to use calorimetry data to determine enthalpy changes during phase changes and chemical reactions.

Worksheet

Q1:

When solid ammonium nitrate dissolves in water, the solution becomes cold. This is the basis for an “instant ice pack”:

When 3.21 g of solid dissolves in 50.0 g of water at in a calorimeter, the temperature decreases to . Assuming that the water has a specific heat capacity of :

Calculate the value of q for this reaction

What is the molar enthalpy for the dissolution of ammonium nitrate in water?

Q2:

Calculate, to 2 decimal places, the enthalpy change produced from the thermal decomposition of 126 g of magnesium carbonate, its molar mass is 84.313 g/mol, under constant pressure according to the given equation.

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