13 - Solutions and Colligative Properties

[@alifaraj312]

MY gene chem prep for the MCAT is almost done, and all what I've learned is based of your videos. i don't know what i would've done without this great god sent man. thanks a lot.

[@ChadsPrep]

Glad you're finding this all helpful Ali and best wishes on that beast they call the MCAT!

[@_sqwid]

Hey did u pass at least?

[@chineloigbo1894]

I love this!!!!!!!!!!!!

[@ChadsPrep]

Glad you're finding these helpful Chinelo!

[@Kattiling]

This video is extremely helpful, thank you!

[@ChadsPrep]

Glad to hear it, Katherine - you're welcome!

[@EuropeEduVoyagewithZ.S]

Sir, I,m feeling really Cool after watching your lecture.(Cool)😊

[@ChadsPrep]

Excellent!

[@rachelmanavi4819]

this is so helpful, thank you very much

[@ChadsPrep]

Glad it was helpful, Rachel!

[@Chemcrown]

good job sir

[@ChadsPrep]

Thanks!

[@Chemcrown]

welcome sir

[@SakeenaManzoor-u4y]

Sir when water molecules are present in gaseous phase as we exert pressure on them they become liquify as the hydrogen bonding among water molecules become significant but if we talk about the O2 gas that is dissolved inside the sea breath by the fish sir how do oxygen gas dissolve in sea ??? What type of intermolecular forces do exist among O2 molecules present above sea which make them liquify on increasing its partial pressure above the sea???

[@ChadsPrep]

Oxygen and other gases are dissolved in sea water in gaseous state rather than liquid state. Not all oxygen dissolves into sea water by air, some is released by plants. There are a few factors at play at the ocean surface which result in atmospheric oxygen becoming dissolved in seawater including wave motion. The ocean surface is dynamic and the amount of oxygen that can dissolve in the seawater depends on temperature, pressure, and other dissolved solutes. The polar water molecules induce a dipole in the oxygen molecule which holds it in solution - so the intermolecular force is permenant dipole - induced dipole interaction.

[@SakeenaManzoor-u4y]

Sir water molecules in the air induces a dipole in O2 molecule or water molecules inside the sea induces a dipole in O2 molecule ???? .And sir if O2 and all other gases dissolved in gaseous phase rather than liquid state then sir how they form a homogeneous mixture with uniform appearance through out although they are still gas inside the water?????

[@ChadsPrep]

In the sea, and yes, seawater is a homogenous mixture including the dissolved gases

[@SakeenaManzoor-u4y]

@@ChadsPrep thank u dear Prof you are my best teacher who can solve my problems 🥰🥰🥰🥰

[@SakeenaManzoor-u4y]

Sir well if water freezes at 0 degree celceus then for an other substance the freezing point is -2 degree celceus then when we find the change in freezing point as it always go down by adding a solute so the change will be positive how ?????

[@ChadsPrep]

Assuming this is about the 2m NaCl example? Can you give me the time in the video for the statement that you are confused about as your question is a little unclear.

[@SakeenaManzoor-u4y]

@@ChadsPrep sir l want to say that we have to cool down a substance to make it freeze so on the addition of solute to a solid as impurity its freezing point will go down compare to a normal freezing pt then the final freezing pt must be negative and the initial freezing pt before adding impurity(solute) for any other substance except water e.g it is -2 degree celceus is it necessary for a substance that its initial freezing pt should be in a negative sign?

[@ChadsPrep]

It is not always true that the final freezing point on addition of solute is negative, just that it is lower than the pure solvent. In the case of water being the solvent which freezes at zero degrees, then yes, adding solute will result in a negative freezing point, but with other solvents that have freezing point above zero this might not be the case.

[@johnbeu3671]

thank you👊

[@ChadsPrep]

You're welcome!

[@kadermmud3884]

Well

[@ChadsPrep]

👍

[@jeanettetsehla7754]

You just covered my entire Semester test 2 notes in less than an hour. Something that takes my lecturers 5 weeks in 2 hours classes 3 times a week😂 Thank you

[@ChadsPrep]

You are welcome!

[@ginaye6782]

This is helping me for my mcat! Thank you!!

[@ChadsPrep]

You're very welcome Gina! Best wishes on that crazy TEST!

[@thatbossguy123]

Really awesome comprehensive video! Thanks!

[@ChadsPrep]

You're welcome and glad you found it helpful!

[@WrathCODM]

amazing lecture

[@ChadsPrep]

Thanks!

[@maxweinberger9544]

These videos are awesome, keep up the great work man!

[@ChadsPrep]

Glad you like them, Max - appreciate the feedback!