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I have a question about Ksp and L'Chateliur's Principle.

Lets says we have the following:

NaCl(s) ----> Na+(aq) + Cl-(aq)

If we add more NaCl(s), the equilibrium does now shift since (s) and (l) do not affect Keq. In addition, the reaction does not shift either b/c L'Chateliur's Principle shifts are not affected by (s) or (l). But what about Q. Q is the [P]/[R] at any time. If we add more solid, don't we in fact increase the value of Q. If so, can't we then compare Q and K to see which way the reaction shifts and/or if we can still dissolve more solid?

Thanks.

I have several questions about the menstrual cycle and would appreciate some clarification. Thanks.

1. Upon birth, a female child is born with primary oocytes. At puberty, primary ooctyes become secondary oocytes. Now it is at menstruation that each of the secondary oocytes are released from the follicle and the whole process occurs. My quest is whether all of the primary oocytes are converted into secondary oocytes at puberty or it is only that primary oocytes start to be converted at each menstrual cycle? I think that the latter is more correct and if so, that means that a female has both secondary and primary oocytes before mensturation. Is there a time or ratio that details when a primary oocyte becomes a secondary oocyte-- is it 3 hrs b/f menstruation?

2. You only form a blastula if 2ndary oocyte is fertilized, correct? So if the secondary oocyte is not fertilized, it remains trapped in Meiosis II since it requires a sperm to tell it to finish Meiosis II. Since it takes around 10 days for the blastula to implant if egg is fertilized, but when it is not, then by Day 23,the corpus luteum starts to degrade since there is no hCG to maintain it, correct? You also have no progresterone to maintain the lining and so there is sloughing off. If that is the case, then how does the body rid itself of the secondary oocyte and where is it by Day 23-- abdominal cavity still?

3. Is there no more corpus luteum by the second trimester since the placenta takes over and makes estrogen and progesterone?

4. Before ovulation, there is a small amount of Estrogen that is secreted by the mature follicle that stimulates contraction and negative feedback to GnRH and prevents release of LH and FSH. By ovulation, you have a buildup of Estrogen and so the high levels of Estrogen go to stimulate LH and FSH release and thus you have the spike at ovulation? Is it the increased estrogen levels that stimulate the release of LH?

If that is correct, then when someone is on the pill (which contains low levels of estrogen and progesterone), how does the pill prevent the increase in Estrogen levels from the mature follicle? Also how does a person on the pill menstruate but not ovulate-- is it that the follicle never pops and so the secondary oocyte is not released, but the whole follicle dies by Day 23 with the secondary oocyte within it?

Thank you.

I am trying to understand exactly what the Van der Waals equation states about the Pressure and Volume of a real gas compared to an ideal gas. Based on the equation, I think that P(ideal)>P(real) because the ideal gas needs to overcome the IMF of attraction since ideal gases have no IMFs; and V(ideal)>V(real) b/c ideal gases occupy no volume and had their volume been smaller, the gas particles would succumb to IMFs.

If someone could please correct me if I am wrong and my logic, I would greatly appreciate it. Thank you.

Lidocain pka 7.6
Prolocain pKa 8.4

We are told that a decrease in the amount of base facilitates removal of the local anesthetics, resulting in a shorter duration of action. Which has a more rapid onset?

The answer was that it was Lidocaine because more exists in its base form at body pH. However, this seems counterintuitive since both pKa's are higher than the pH. I do remember reading a rule somewhere that if pKA>pH, then the group is considered to be in its acidic form when attached to an aa, but I don't know if that rule only applies to aa and what that rule means. Could someone please clarify it?

I am confused about what the difference is between Bond Energy, Enthalpy of Formation, Hess's Law and Enthalpy? The reason being that they all involve heat (ie enthalpy) as a measurement. Enthalpy I know is the heat present in a system. Enthalpy of Formation is the formation of a compound from elements in their most stable/standard state. Bond energy is the heat added to a system to break bonds and then heat is released when new bonds are formed. But the answer that you get in the end of the day is still in terms of enthalpy, correct?

If so, then does that mean that if a reaction is exothermic, heat is released, surroundings get hotter, and the bonds formed are stronger than the bonds broken because more heat/energy is released than was used to initially break the bonds?

Also, if one compares bond strength (such as in sp>sp2>sp3), does that mean that the stronger bond is more exothermic, the products are at a lower energy and are more stable than the reactants? To make this claim, we would use Hrxn = E(bonds broken) - E(bonds formed), correct? Then when do we use delt H= products - reactants?

I would greatly appreciate it if someone could please clarify my confusion. Many thanks.