Welcome to the Thermochemical Equations debriefing

Answer the questions below, and click on the Check buttons when you are ready.

1. Suppose you mix 10.0 mL of 1.00 M HCl and 10.0 mL of 1.00 M NaOH in a coffee cup calorimeter with a 100.0 mL reservoir of water. If the initial and final temperatures in the calorimeter are 25.00 and 26.11 ºC, what is the enthalpy change for the reaction

H+ (aq) + OH- (aq) H2O (l)     DH = ?

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Answer (include units!):


Correct!
The DH = -55.7 kJ.
While numerically correct, your answer has the wrong number of significant digits. Try again.
While numerically correct, your answer has the wrong sign. Try again.
Remember to include the volume of water added by the acid and base! Try again.
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2. Hydrazine (N2H4(l)) is commonly used as a rocket fuel. Calculate the enthalpy change when 1.00 kg of hydrazine is burned in a rocket according to the equation below. Click on the Thermodynamics icon at right to see the table of thermodynamic quantities.

N2H4 (l) + O2 (g) N2 (g) + 2 H2O (g)

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Answer (include units!):


Correct!
The DHº = -16,700 kJ.
While numerically correct, your answer has the wrong number of significant digits. Try again.
While numerically correct, your answer has the wrong sign. Try again.
That is incorrect. Please try again.

Congratulations!

You have completed the Thermochemical Equations module.

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