1) Determine the Kc for the following experimental conditions:
compound A+compound B --> Compund D
Compound: A B
M 0.003 0.0023
Volume used: 5 mL 8 mL
Total volume = 25 mL, using graph 2 and a %T of 24 for compund D molecular weight compund D = 535 g/mol
2) Determine Kc for compound D at a %T of 65 with the same initial concentrations as question 1 and graph 2
3) A group used 15 mL of compound Band 8 mL of compound A with the total volume of 2.5 mL and the %T was 5. Using graph 2 determine Kc.
The chart for graph 2 gives this information:
y = absorbance= 0.069, 0.324, 0.594, 0.864, 1.134, 1.404, 1.674
x = concentration (mg/mL) respectively= 0.01, 0.06, 0.11, 0.16, 0.21, 0.26, 0.31.
There is a y=5.3679x + 0.0073 equation also.
To solve these questions and determine the Kc values, follow the steps below:
1) For question 1, we need to determine the concentration of compound D in terms of mg/mL. We can use the equation y = 5.3679x + 0.0073 to convert the absorbance (y) to concentration (x).
Find the corresponding absorbance value for compound D at %T 24 in the chart:
%T = 24 corresponds to absorbance = 0.324
Substitute the absorbance value into the equation:
0.324 = 5.3679x + 0.0073
Solve for x:
x = (0.324 - 0.0073) / 5.3679
Now, we have the concentration (x) of compound D in mg/mL.
Next, calculate the concentrations of compounds A and B in mol/L. This can be done using the given masses and volumes:
For compound A:
Mass = 0.003g
Volume = 5mL
Convert mass to moles:
Moles A = mass A / molar mass A
Molar mass A can be found using the periodic table.
For compound B:
Mass = 0.0023g
Volume = 8mL
Convert mass to moles:
Moles B = mass B / molar mass B
2) To find Kc for compound D at %T 65 with the same initial concentrations as question 1, follow the same steps as in question 1. Use the respective absorbance value from the chart for %T 65 to calculate the concentration of compound D. Then, substitute the concentrations of A, B, and D into the formula:
Kc = [D]^n / [A]^m * [B]^p
3) For question 3, the process is the same as in question 1. Use the given volumes of compounds A and B, along with the total volume, to find their concentration in terms of mg/mL. Then, use the respective absorbance value for %T 5 to calculate the concentration of compound D. Substitute the concentrations of A, B, and D into the formula to find Kc.
Remember, in all the calculations, it is important to keep the units consistent (e.g., g/mol for molar mass, mg/mL for concentration, etc.) and use the correct coefficients from the balanced chemical equation to determine the values of n, m, and p in the Kc expression.