Answer to Question #231545 in General Chemistry for Naz

Question

A student is determining the enthalpy of solution for ammonium nitrate by adding ammonium nitrate to a calorimeter and measuring the temperature change.

The accepted value is Hsol'n = 25.7 kJ/mol

A student, not paying attention, adds 1.5g of ammonium nitrate instead of 1.0g. When they perform their calculations, they use 1.0g as the mass.

Will their calculation result in an answer that is higher than the accepted value or lower? Explain.

Answer 1

• Higher than the accepted value.
• Explanation: The temperature change for 1.5g of ammonium nitrate will be relatively higher than that of 1.0g of ammonium nitrate. Since the enthalpy change is found using the formula q = mc∆T, a higher change in temperature will give a relatively higher enthalpy.