Calorimeter lab. What is the change in enthalpy for magnesium after the reaction with vinegar?
vinegar is 60ml
magnesium is 0.7g
T1 = ?
T2 = 31.8°C
find the initial temperature if 123.4 KJ energy has been released.
THIS IS ALL THE INFORMATION THAT I GOT FROM MY TEACHER I SWEAR.
Mg + 2HC2H3O2 ==> Mg(C2H3O2)2 + H2
mols Mg = 0.7/24.3 = about 0.0288
You ask for two things; i.e., you ask for enthalpy of Mg AND initial temperature. Here is how you do Ti. Assuming specific heat AND density vinegar are the same as a solution of water then
q = mass soln x specific heat soln x (Tfinal-Tinitial)
-123400 J = 60 g x 4.184 J/oC*g x (31.8 - Ti)
Substitute and solve for Ti.
For the enthalpy, dH is -123.4 kJ for 0.0288 mols Mg.
So -123.4 kJ x (1 mol/0.0288 mol Mg) = ? kJ/mol
To determine the change in enthalpy for the reaction between magnesium and vinegar, you would need to perform an experiment using a calorimeter. However, based on the information you provided, it seems that the necessary details for calculating the change in enthalpy are incomplete. In order to accurately calculate the change in enthalpy (ΔH) for a reaction, you would need the following information:
1. Mass of magnesium (0.7g): This is given in the information you provided.
2. Volume of vinegar (60ml): This is also given in the information you provided.
3. Initial temperature (T1): This is missing and needs to be provided.
4. Final temperature (T2): Given as 31.8°C.
5. Energy released during the reaction: Given as 123.4 kJ.
To calculate the change in enthalpy, you would typically use the equation:
ΔH = q / n
Where:
- ΔH is the change in enthalpy,
- q is the heat absorbed or released by the reaction,
- n is the amount of substance present in the reaction.
To determine q, the heat absorbed or released, you would use the formula:
q = mcΔT
Where:
- q is the heat absorbed or released,
- m is the mass of the substance (magnesium in this case),
- c is the specific heat capacity of the substance,
- ΔT is the change in temperature (T2 - T1).
However, without the initial temperature (T1), it is not possible to calculate the change in enthalpy. It is important to note that the information you provided is insufficient to accurately determine the change in enthalpy for the reaction between magnesium and vinegar.