111 of 115 people found the following review helpful:
3.0 out of 5 stars
CDs Contain Errors; Publisher Has Done Nothing to Correct Them, January 24, 2010
This review is from: Examkrackers MCAT Audio Osmosis with Jordan and Jon (Audio CD)
(Update 2011/06/07 - I increased the star rating to three, as I think, in hindsight, one was a bit harsh)
I bought these CDs for my wife, who is studying for the MCAT exam. This, along with hundreds of dollars worth of other assorted books and materials to help her prepare for it. We do not have a lot of money to spend on these materials as we are both university students (well, I just graduated) but we are willing to pay a high price for these items because we consider the benefit that my wife receives from them - a higher MCAT score - very important to our family's future success and a good investment. We feel the high price can be justified.
What I cannot tolerate is having recently discovered a list of numerous factual errors on these CDs, which I have verified myself by listening to them. This would not bother me so much if ExamKrackers had bothered to press a second edition of the CDs to correct these errors (I understand that people make mistakes, which is one of the main reasons for continuing editions of educational materials) or put a paper insert into the current CD set detailing these mistakes. The best they can do is admit to the errors on their website forums as "errata".
Maybe I'm still a little grumpy from spending so much money on numerous studying materials, but I felt the need to write this low-star review and get this information out to others so that intelligent buying decisions can be made by all.
Below is the list of errors. Note that I did not compile this list, but am simply sharing it for the benefit of others.
CD #3 Track 17: The terms 'cohesive' and 'adhesive' are reversed when Jordan says:
"The cohesive forces of water to glass are greater than the adhesive forces of water to water. The cohesive forces can cause a water column to climb the glass of a thin test tube. This is called capillary action. If the adhesive forces are stronger than the cohesive forces, like mercury in a glass test tube, the miniscus is convexed and will be pulled downward in a thin test tube."
He should have said:
"The adhesive forces of water to glass are greater than the cohesive forces of water to water. The adhesive forces can cause a water column to climb the glass of a thin test tube. This is called capillary action. If the cohesive forces are stronger than the adhesive forces, like mercury in a glass test tube, the miniscus is convexed and will be pulled downward in a thin test tube."
All other references to cohesive and adhesive are correct.
Cohesive forces are the forces between molecules within the fluid, such as water-to-water forces. Adhesive forces are the forces between the molecules of the fluid and the container, such as water-to-glass.
---------------------------------------------------------------------------------------------------
CD #4 Track 2: Coulomb's law constant is 8.9x10 to the positive 9 not negative 9.
This edit is courtesy of one of our astute listeners. Thank you for the edit.
---------------------------------------------------------------------------------------------------
CD #4 Track 18: When discussing the critical angle Jordan says "If the light is moving from a lower idex of refraction to a higher index of refraction..."
Total internal reflection occurs when light tries to move from a medium with a HIGH index of refraction to a medium with a LOW index of refraction and the angle of incidence is so great that all the light is reflected back into the high indexed medium.
In the same discussion, Jon says "The larger index of refraction must be on the top of the ratio." when solving for the critical angle with Snell's law. The opposite is true. The larger index of refraction must be on the bottom of the ratio, so that the ratio is a fraction less than one.
--------------------------------------------------------------------------------------------------
CD #5 Track #7: Stand alone timers are no longer allowed on the MCAT. You are limited to a watch.
--------------------------------------------------------------------------------------------------
CD #6 Track 5: Jon says "The equilibrium expression changes with temperature, but is not affected by a catalyst or by concentrations." He should have said "The equilibrium CONSTANT changes with temperature, but the EQUILIBRIUM EXPRESSION does not. Neither the equilibrium expression nor the equilibrium constant is affected by a catalyst or by concentrations. "
---------------------------------------------------------------------------------------------------
CD #6 track #15: Jordan says that the net heat transfer rate is proportional to... ...the temperature difference between the body and the environment raised to the fourth power. net heat transfer = sigma*epsilon*A*(T^4 - Te^4).
The net heat transfer is actually proportional to
T^4 - Te^4) NOT (T-Te)^4
At low temperture differences, Newton's law of cooling says that the rate of cooling of a body is approximately proportional to the temperature difference between the body and the environment.
---------------------------------------------------------------------------------------------------
CD #7 Track 2: While discussing melting Jon says "It is interesting to relate thermodynamics to the heat curve... ...But the enthalpy change is NEGATIVE"
Jon should have said "It is interesting to relate thermodynamics to the heat curve... ...But the enthalpy change is POSITIVE" Both enthalpy change and entropy change are positive during melting. Everything else in the track still applies. If both entropy and enthalpy change are positive, delta G depends upon temperature.
---------------------------------------------------------------------------------------------------
CD #7 Track #8: Jordan says "Lewis acids: donate; bases: accept." This is backwards. Lewis acids accept a pair of electrons and Lewis bases donate a pair of electrons.
---------------------------------------------------------------------------------------------------
CD #7 track #10: Jordan says that the pH of a solution with a hydrogen ion concentration of 3.6x10^-4 is 4.5. It is 3.5.
---------------------------------------------------------------------------------------------------
CD #7 Track #11: Jordan says "The log of A times B equals the log A times the log of B." He should say "The log of A times B equals the log of A plus the log of B."
---------------------------------------------------------------------------------------------------
CD #7 Track 26: Jon says "..the arteriole red blood cells contain fewer chloride ions than venous red blood cells."
If Jon had been thinking correctly he would have said "..the arteriole red blood cells contain MORE chloride ions than venous red blood cells."
---------------------------------------------------------------------------------------------------
CD #7 Track 30: Jordan says "If delta G zero is positive, K is greater than one. If delta G zero is negative, then K is less than one." This is backwards. A positive delta G zero indicates a K less than one, and a negative delta G zero indicates a K greater than one.
---------------------------------------------------------------------------------------------------
CD #8 Track 23: Jon says "...dragging the second tRNA to the P site, adn exposing the P site for yet another tRNA."
Jon should say: "...dragging the second tRNA to the P site, and exposing the A site for yet another tRNA."
---------------------------------------------------------------------------------------------------
CD #8 track 23: DNA and RNA are read 5 to 3. Anticodons are an exception and they are read 3-5. This track says that the anticodon is read 5 to 3. This is incorrect. This knowledge is very unlikely to be tested by the MCAT.
---------------------------------------------------------------------------------------------------
CD #9,Track 50: says that the oocyte undergoes meiosis 1 and 2 after penetration by the sperm.
This is incorrect for humans. The correct process is as follows:
"Oogenesis begins in the ovaries of the fetus. All the eggs of the female are arrested as primary oocytes at birth... ...Shortly before the primary oocyte is released from the follicle during ovulation, the nucleus divides by meiosis to become the secondary oocyte... ...The entry of the sperm causes the cortical reaction, which prevents other sperms from fertilizing the same egg. Now the oocyte goes through the second meiotic division releasing a second polar body. Fertilization occurs when the nuclei of the egg and sperm fuse to form the zygote."
---------------------------------------------------------------------------------------------------
CD #12 Track 3: Jordan says "isn't there a way to add the halogen to the MOST substituted carbon?" and Jon says, "with peroxides... HYDROGEN adds the most substituted carbon"...
Jordan should say "Halogen to the LEAST sustituted carbon".
--------------------------------------------------------------------------------------------------
CD #12 track #6: Hydroboration.
Jordan says, "Now is there a way to hydrate an ALCOHOL with anti-markovnikov addition."
Jordan should have said ALKENE instead?
---------------------------------------------------------------------------------------------------
CD #10 Track 8: The track incorrectly reads: "nutrients are absorbed into the enterocytes of the small intestines mainly in the DUODENUM"
Duodenum does mostly digestion and jejunem and ileum do most of the absorption.
Help other customers find the most helpful reviews
Was this review helpful to you? Yes
No
