chem lab write up how hot is that flame

chem lab write up how hot is that flame - Title: How Hot is...

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Title: How Hot is that Flame? Experiment #6 William Matthew Speight Locker Number: J20-4 Chem 1A, Section 450, Rebecca Petit Purpose: To determine the enthalpy, or heat of reaction, associated with the reaction: Mg (s) + ½ O 2 (g) MgO (s) through the process of calorimetry and the use of Hess’s Law. Methods: Since the enthalpy of 2H 2 (g) + O 2 (g) 2H 2 O (l) is known the enthalpies of the reactions: Mg (s) + 2HCl (aq) MgCl 2 (aq) + H 2 (g) and MgO (s) + 2HCl (aq) MgCl 2 (aq) + H 2 O (l) must be found in order to use Hess’s Law. First, the heat capacity of the calorimeter was determined. This was completed by solving for k cal in the equation: (m RT H20 )(T f – T RT )(C w ) + (m cold H2O )(T f – T cold )(C w ) + (k cal )(T f – T RT ) = 0. Water at room temperature was used to fill the calorimeter about half way. The mass and temperature of the water was found. Then, temperature of ice-cold water was found. The calorimeter was filled with the ice-cold water until it was about three-quarters full and the lid was put on. The mass of the added cold water was found. The calorimeter sat until the temperature of the water had leveled off. This was the final temperature. Assuming all heat (and energy) in the process was contained, the heat absorbed by the cold water was equal to the heat lost by the room temperature water and the calorimeter. For this process, the reaction is the system and the solution and calorimeter are the surroundings. Dispose of the water in the calorimeter. Next, the enthalpy of the reaction: Mg (s) + 2HCl (aq) MgCl 2 (aq) + H 2 (g) was found. This was completed by using the equation: ΔH = q/mol Mg . 100 mL of 1M HCl was measured and poured into the calorimeter. The mass and temperature of the HCl was found. 0.2500g of magnesium was weighed and added to the calorimeter. The lid was sealed. The calorimeter was continuously swirled and temperature readings were taken until a stable temperature was reached. q was found by using the equation: q = (m
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This note was uploaded on 03/13/2009 for the course CHEM 1A taught by Professor Nitsche during the Spring '08 term at University of California, Berkeley.

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chem lab write up how hot is that flame - Title: How Hot is...

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