Van der Waals Forces
ฝัง
- เผยแพร่เมื่อ 9 มิ.ย. 2024
- For Employees of hospitals, schools, universities and libraries: download up to 8 FREE medical animations from Nucleus by signing up for a free trial at: nmal.nucleusmedicalmedia.com/b...
#VanDerWaals #molecules #MolecularAttraction
SCIENCE ANIMATION TRANSCRIPT: In this video, we'll discuss Van der Waals forces. Van der Waals forces are forces of attraction between molecules that are very close together. These forces between molecules are much weaker than the chemical bonds between the atoms holding a molecule together. Let's see how Van der Waals forces work. Molecules are electrically neutral because they have equal numbers of positively charged protons in the nucleus and negatively charged electrons outside the nucleus. In addition, some molecules are also polar. What does this mean? Well, polar molecules have permanent poles of electrical charge like a magnet because the electrons are unevenly distributed around the molecule. How does this happen? Let's look at an example of a polar molecule, water. A water molecule, or H2O, consists of two hydrogen atoms and one oxygen atom. When a water molecule forms, both hydrogen atoms bond with the oxygen atom by sharing their electrons with the oxygen atom. This completes both oxygen's outer electron shell, which can hold all eight electrons, and hydrogen's outer shell, which can hold two. However, the electrons aren't shared equally between the atoms because the oxygen atom attracts the electrons more strongly than hydrogen. As a result, a partial negative charge develops around oxygen because there are more negatively charged electrons around the oxygen side of the molecule. In comparison, fewer electrons around the hydrogen atoms create a partial positive charge on the hydrogen side of the molecule. This unequal sharing of electrons creates opposing poles of electrical charge on either side of the two bonds that hold the atoms together. Because of the opposite poles, these bonds are called polar covalent bonds. And since a water molecule is angled or bent with both of the hydrogen atoms on one side and the oxygen atoms on the other side, the molecule as a whole also has opposite poles and therefore is referred to as a polar molecule. Now, when polar molecules are near each other, a Van der Waals force of attraction between the molecules occurs because of their oppositely charged poles. In this example, the attraction of a polar molecule's negative pole to the positive pole around hydrogen atoms in water is a particularly strong type of Van der Waals force called a hydrogen bond. Hydrogen bonds only occur in polar molecules between hydrogen in one molecule and oxygen, nitrogen, and fluorine in the other. If a molecule doesn't have permanent poles of opposite electrical charge, it's called a non-polar molecule. However, non-polar molecules can become polar for very brief moments since the locations of electrons around atoms are constantly changing. This means the molecule can have a temporary negative pole on the side where there are momentarily more electrons, and a temporary positive pole on the opposite side where there are fewer electrons. The momentary concentration of electrons in this molecule's negative pole can repel the electrons in a nearby molecule toward its opposite end, making the neighboring molecule polar as well. The oppositely charged poles of adjacent molecules attract each other, forming weak connections between them called Van der Waals forces. Van der Waals forces explains two important properties: cohesion, the attraction between like molecules within a substance, and adhesion, the attraction between unlike molecules in different substances. An example of cohesion is when opposite poles of water molecules are attracted to each other but not to the surrounding air. This creates an inward force allowing water to bead up and form water droplets. Adhesion, the force of attraction between unlike molecules, explains how geckos are able to climb on slick, flat surfaces. Although each molecular connection is very weak, geckos can form millions of them between the molecules within the microscopic hairs on each foot and the molecules in the climbing surface. These connections add up to more than enough adhesion force to support the gecko's weight. In summary, Van der Waals forces are forces of attraction between molecules. They are not the same as chemical bonds between atoms within a molecule. They can occur in permanently polar molecules, such as water, and in non-polar molecules when they become briefly polar due to the changing positions of electrons. A hydrogen bond is a strong Van der Waals force between a polar molecule containing hydrogen atoms and the negative pole of another polar molecule. Van der Waals forces account for cohesion, the attraction between like molecules within a substance, and adhesion, the attraction between unlike molecules in different substances. [music]
NSV16025
I really like the animation. It made it better to understand
IDK how much could i praise you for this explanation, really beautiful and explaining video, thanks to you sir!
When we had this topic in school i asked how does it work and why can some of those things happen, teacher didnt know so this was realy nice and im thankful.
Its important to understand not just learn it by hard.
THank you so much. It was great video with great animations. Thanks to you i won't fail my test.
Don't worry!You will pass it 😧😎
Great video with nice and simple explanation, just what i needed, thank you so much.
Really helped me understand the concept. THANKS!
This video was really great and helped me with something on my MSc Physics course. Thank you
Thanks it will help me to study
Very much helpful. Understood it in a better way 👌
This channel is just amazing.
amazing work. well done 👏
Thank you for your effort. Much appreciated
Thankyou for this explanation… really cleared mind of doubts
why so much underrated... :(
you explain good as f..
Best explanation ever!! Great video for visual learners like me. Thank you!!
Outstanding🎉 So easy to understand and remember 😊
Appreciate this person........
Well explained 👌
Thankyou
Very helpful
So thankful
This takes me back to 2006 high school engineering...❤
fantastic video!
Please make video on dipole induced dipole force,London dispersion forces.I am waiting for such conceptive videos.
I loved it!
I love the way you draw molecules
I really loved it
Very well explained
What a quality work . well done 👍
Extremely helpful ❤
Thank you dear
thank you so much. this really help alot!
xxx
Very nice info 👍
Hey, thanks for this video! Explained very clearly :)
Brilliant explanation 👍🏻
thanks for this video very well explained
nice 3d display great
Explained so well thankyou
Thank you so much 🙏
excellent sir
It was very nice video
Thank u 🥰🥰it's all became so easy
Nice explanation in a good n simple way
Thanks for the video😊✨️
Excellent explanation
Thank you very much sir.
Wow after 20 years this video finally made perfect sense of chemistry to me
DAMN this was good!!! GREAT explanation!!!
Nicely explained...🎉
Brilliant. Thanks to U.
Thank you very much if it possible you should explain about anion and cation
Whats the differnce between gaz de Van der Waals and PV= ZR T
Thanks a lot!
thank you very much 🙏🙏
Thank you.
Amazing❤❤
That was awesome
Wonderfully explained, really helpful
Thank you🧡
Thank you
I loved it!❤😍
I feel like I just took a trip with Miss Frizzle back to Jr. High to review a topic that absolutely flew over my head at the time.
I’m trying so hard to understand this part,but I just can’t
I suggest you watch The Organic chemistry tutor's videos on intermolecular forces it'll help you understand better. Hope this helps 👍
반데르발스 힘을 설명하는 것이 혼동되어 사용되어서 정확한 구분을 못하고 있었는데 이 영상으로 깔끔하게 정리할 수 있었습니다
thanks
we want more videos and quizzes based on biology ncert 🙏 ❤️ Love from India
I watched a gecko video where they mentioned this force. Very well explained for somone who's really bad at physics and find it super boring. Thanks my guy
thanks i learned something, really clear.
كفو فعلا
Gooooooood
When you twist it together do the electrons get velcroed?
im french and i understood better than in class with my teacher. what the heck
or chains of connectet atom by atoms
how did we figure this stuff out, like oh my god you are telling me my body is made of a magnetic liquid created by tiny particles that have little merry go rounds inside of them that somehow want to be together really bad? if the van der waals force forms only in polar molecules and in special occasions, how do we have other objects? that must be tons of molecules sticking together? is that some other force?
What what is electrons
Water molecule: magnetic dipole
Water has ionic bonds we say, do not we. We do not call it van der waals?
First of all atoms of water are bonded with covalent bond and each water molecule is Interconnected with H-bond.
that's look like template of mytosis🤨🤨🤨🤨
They are atoms not cells
From : Cumhuriyet Sivas Türkiye
Hydrogen is not a bond !!! It is a force of attraction it is different !!
where wzory miernoto ez
Terrible. Visuals are inaccurate and often confusing. When they start talking about "location of an electron" i couldnt continue watching this.
damn baby
Thank you