Predicting Organic Reaction Equilibrium From pKa Values

This lecture we focus on using the pKa values for various organic acids to predict which side of an organic reaction will be favored at equilibrium.

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[Yarthephilomath]

This channel helps me prepare for my entrance exam and tbh you explain concepts I forgot about and am not as familiar with thats explained in more difficulty in the reference book with so much ease! Thank you for your hardwork

[Azonderr]

ATP stores energy through its ability to lose a phosphate group to form ADP in the following reaction

At body temperature, the thermodynamic values for ATP hydrolysis are as follow.
ΔG = –30kJ/mol
ΔH = –20kJ/mol
ΔS = 34kJ/mol

Glycolysis is an energy-liberating process (ΔG = –218kJ/mol, ΔH = –20 kJ/mol) that is coupled with the conversion of two ADP molecules into two ATP molecules according to the following reaction.


How much heat, in joules, is released when 4 * 1019 molecules of ATP are converted to ADP via ATP hydrolysis?

[bestdancevideos]

Yours Video's Was Superb
But
You Are Upload Column Chemistry

[sydneyrudisill]

Abstract:
The purpose of the experiment was to confirm the melting point of pure urea and trans-cinnamic acid, to examine the effects of impurities on melting points, and to determine the identity of an unknown sample using a melting point. Intermolecular forces impact the depression of melting points, specifically impure compounds. Impurities were seen through the depression of the melting points. This was confirmed with the results of an unknown + trans-cinnamic acid which had a melting point of 100ºC. That is less than the predetermined melting point of trans-cinnamic acid, 133ºC. It was confirmed that the melting point for urea and trans-cinnamic acid is 133ºC.

Introduction:
The reasoning for taking the melting point of both urea and trans-cinnamic acid is to identify how pure the compound is. A melting point is done by packing the compound into a small glass tube that is then placed into the melting point apparatus. The sample is slowly heated up until it is melted. The temperature was recorded. That temperature was then used to determine whether or not it is a pure compound. The theory of melting point is that it takes less energy to disturb the crystal lattice when impurities are present. Impurities were seen through the depression of the melting points. The depression of the melting point occurs because of intermolecular forces. This was seen in the sample of an unknown + trans-cinnamic acid which had a melting point of 100ºC. The melting point of trans-cinnamic is 133ºC, there was a significant decline in the melting point.

Chemical Index for the Melting Point of Urea and Trans- Cinnamic Acid

Chemical name
Structure
Molecular Weight
Melting Point
Special Note
Urea

60.06 g/mol
133ºC


Trans- Cinnamic Acid



148.1586 g/mol
133ºC
unsaturated carboxylic acid


Methods:
A sample of urea was packed into a small glass tube. The melting point apparatus heated slowly. The same process was done for the trans-cinnamic acid sample. Additional 6 more melting points were taken. The melting point of 80% trans-cinnamic acid / 20%urea, 80%urea / 20%trans-cinnamic acid, 50% trans-cinnamic acid / 50%urea, an unknown, and unknown + urea, and finally and unknown + trans-cinnamic acid.

Data and Results:
It was found that the trans-cinnamic acid sample was pure, this is proven by the recorded melting point of 133ºC. The urea sample was pure, this is proven by the recorded melting point of 133ºC. The melting point of the 80% trans-cinnamic acid / 20%urea sample was 130.1ºC. The melting point of the 80%urea / 20%trans-cinnamic acid sample was 131.5 ºC. The melting point of the 0% trans-cinnamic acid / 50%urea sample was 112.2 ºC. The melting point of the unknown sample was 133ºC. The melting point of the unknown + urea was 132.1ºC. Finally, the melting point of the unknown + trans-cinnamic acid was 100ºC.

Discussion:
The purpose of the experiment was to confirm the melting point of pure Urea and Trans- Cinnamic Acid. Through the experiment, it was able to conclude that the melting point for water was 133ºC. A potential source or error while talking about melting points is not keeping a close eye, this could lead to not seeing the sample melt at the correct temperature. It was clear that there were impurities in the samples. 80% trans-cinnamic acid / 20%urea sample was 130.1ºC, 80%urea / 20%trans-cinnamic acid sample was 131.5 ºC, 0% trans-cinnamic acid / 50%urea sample was 112.2 ºC, unknown + urea was 132.1ºC, unknown + trans-cinnamic acid was 100ºC. Looking at the sample of an unknown + trans-cinnamic acid which had a melting point of 100ºC, compared to a sample of pure trans-cinnamic acid which was 133ºC, there was a 33ºC in the melting point. This implies that a significant amount of the impurities in the unknown + trans-cinnamic acid sample.

[Azonderr]

If 22.29 mL of a 0.149 M NaOH solution are needed to titrate 0.277 grams of an unknown monoprotic acid. What is the molar mass of the acid? Express your answer in g/mol and use three significant figures.