Help with lab report
Need Help finishing my lab report.KNOWN VALUES ARE V OF HCL=50ML,M=2.188.V OF NAOH=55.3ML,M=2.088.INTIAL TEMP FOR HCL=22.5C,NAOH IS 23C.this is for part A: Mass of final NACL solution assuming that the density of a 1 M Nacl solution is 1.04 g/ml? Heat actually produced from the HCL-NAOH reaction assuming that the heat capacity of a 1 M Nacl solution is 3.93 J/G.C? Moles of water formed in the reaction? Total theoretical heat expected to be produced by forming the number of moles of water assuming that 57,320 J are produced per mole of water formed? Heat absorbed by the calorimeter(heat expected-heat actually produced)? Heat capacity of the calorimeter(heat absorbed by the calorimeter per degree of temperature change)? For Part B: Total mass of the final solution by adding the mass of intial HCL solution(density of 2 M HCL is 1.03 g/ml)the mass of water (D=1.00g/ml)and the mass of magnesium? Heat required to raise MgCl_2 solution to the max temp assuming that heat capacity of your final mgcl2 solution is 3.97 J/G.C? Heat required to raise the calorimeter to the max temp using the value for the heat capacity of the calorimeter as determined in part A of this experiment? Total heat evolved by the reaction by adding the heats required to raise both the solution and the calorimeter to the max temperature? heat evolved per mole of mg? change in enthalpy for the following specific reaction Mg(s)+2H(aq)>>Mg2+(aq)+H2(g)
Unfortunately i knew the answer to the ones you posted,i just don't know how i can answer the heat capacity one..
You need data for the rise in T when acid/base were reacted. You need rise in T when Mg reacted. Neither of those are shown in your post.
May this question rise again bring forth new light ... i need help
How do you find the moles of water
Ah, the joy of lab reports. Let's tackle these questions one by one, shall we?
For Part A:
1. Mass of final NaCl solution: You can calculate this by multiplying the volume of NaOH solution (55.3 mL) by its density (1.04 g/mL).
2. Heat produced from the HCl- NaOH reaction: Multiply the volume of HCl (50 mL) by its molarity (2.188), and then by the heat capacity of a 1 M NaCl solution (3.93 J/g·°C).
3. Moles of water formed in the reaction: Since the balanced reaction equation is not provided, I'll need that to give you an answer.
4. Total theoretical heat expected to be produced: Multiply the number of moles of water formed (from #3) by the heat produced per mole of water (57,320 J/mol).
5. Heat absorbed by the calorimeter: Subtract the heat actually produced from the heat expected.
Now, let's move on to Part B:
1. Total mass of the final solution: It would be the sum of the mass of initial HCl solution, the mass of water, and the mass of magnesium.
2. Heat required to raise MgCl2 solution: Multiply the total mass of your solution (from #1) by the heat capacity of the final MgCl2 solution (3.97 J/g·°C).
3. Heat required to raise the calorimeter: Same as in Part A, use the heat capacity calculated in Part A.
4. Total heat evolved by the reaction: Add the heats required to raise both the solution and the calorimeter to their maximum temperatures.
5. Heat evolved per mole of Mg: You'll need the balanced reaction equation to answer this one.
6. Change in enthalpy: You can calculate this by using the standard enthalpies of formation for each compound involved in the reaction. Again, I'll need the balanced reaction equation to give you a specific answer.
Remember to provide the balanced reaction equations for the questions that require them, and make sure to double-check your calculations. Should you need further assistance, feel free to ask!
To help you with your lab report, let's break down each question and go step by step. I will explain how to calculate each value using the given information. Please note that I will assume you are familiar with the necessary equations and concepts used in these calculations.
Part A:
1. Mass of final NaCl solution:
To calculate the mass of the final NaCl solution, you need to multiply the volume (V) of the NaOH solution by its density (D). Given that the density of a 1 M NaCl solution is 1.04 g/mL:
Mass (g) = Volume (mL) * Density (g/mL)
Mass NaCl solution = 55.3 mL * 1.04 g/mL
2. Heat produced from the HCl-NaOH reaction:
To calculate the heat produced, you can use the equation:
Heat (J) = q = m * c * ΔT
where m is the mass (g) of the solution (assuming the density of the 1 M NaCl solution), c is the heat capacity (J/g°C), and ΔT is the change in temperature (final temperature - initial temperature).
3. Moles of water formed in the reaction:
The balanced equation for the reaction between HCl and NaOH is HCl(aq) + NaOH(aq) → NaCl(aq) + H2O(l). From the balanced equation, you can see that the stoichiometric ratio between H2O and NaCl is 1:1. This means that for every mole of NaCl formed, one mole of water is also formed.
4. Total theoretical heat expected to be produced by forming the number of moles of water:
You are given that 57,320 J are produced per mole of water formed. So, you can calculate the total theoretical heat expected by multiplying the moles of water formed (calculated in step 3) by the heat produced per mole.
5. Heat absorbed by the calorimeter:
You can calculate the heat absorbed by the calorimeter using the equation:
Heat absorbed by calorimeter = Total theoretical heat expected - Heat actually produced
6. Heat capacity of the calorimeter:
Heat capacity is defined as the heat absorbed by an object per degree of temperature change. To calculate the heat capacity of the calorimeter, you can use the equation:
Heat capacity (J/°C) = Heat absorbed by calorimeter / ΔT
Part B:
1. Total mass of the final solution:
To calculate the total mass of the final solution, you need to add the mass of the initial HCl solution, the mass of water, and the mass of magnesium.
2. Heat required to raise the MgCl₂ solution to the maximum temperature:
You can use the same equation used in Part A to calculate the heat required. Substitute the mass of the MgCl₂ solution (including the mass of initial HCl solution, water, and magnesium), the heat capacity of the final MgCl₂ solution, and ΔT.
3. Heat required to raise the calorimeter to the maximum temperature:
You can use the same equation used in Part A to calculate the heat required. Substitute the heat capacity of the calorimeter (determined in Part A), and ΔT.
4. Total heat evolved by the reaction:
To calculate the total heat evolved, you need to add the heats required to raise both the solution and the calorimeter to the maximum temperature.
5. Heat evolved per mole of Mg:
The balanced equation given shows that 1 mole of Mg produces 1 mole of Mg²⁺. From this, you can determine the stoichiometric ratio between heat evolved and moles of Mg.
6. Change in enthalpy for the specific reaction:
The change in enthalpy (ΔH) can be calculated by dividing the total heat evolved by the number of moles of Mg used in the reaction.
I hope this explanation helps you complete your lab report. If you have any further questions or need assistance with specific calculations, feel free to ask!
I can get you started but I won't do your lab report for you.
HCl + NaOH ==> NaCl + H2O
HCl = 50 mL x 2.188 M = 109.4 mmols.
NaOH = 55.3 mL x 2.088 = 115.466 mmols.
Total volume = 55.3 + 50 = 105.3 mL and mass is 105.3 mL x 1.04 g/mL = 109.51g
This should get you started. Note however, that I don't see a temperature rise from 22.5/23 C AND I don't see a mass of Mg or what you did with the Mg.