Back to chapter

2.12:

קשרי מימן

JoVE Core
Biology
A subscription to JoVE is required to view this content.  Sign in or start your free trial.
JoVE Core Biology
Hydrogen Bonds

Languages

Share

קשרי מימן הם משיכות חלשות מאוד בין אטום אחד בעל מטען שלילי חלקי, אטום אלקטרושלילי כמו חמצן, ואטום מימן בעל מטען חיובי חלקי. בעוד קשרים אלו, הנפוצים ביותר בין מולקולות H2O במים, הם חלשים בנפרד, הם חזקים מאוד במצטבר.

2.12:

קשרי מימן

Hydrogen bonds are weak attractions between atoms that have formed other chemical bonds. One of these atoms is electronegative, like oxygen, and has a partial negative charge. The other is a hydrogen atom that has bonded with another electronegative atom and has a partial positive charge.

Hydrogen Bonds Control the World!

Because hydrogen has very weak electronegativity when it binds with a strongly electronegative atom, such as oxygen or nitrogen, electrons in the bond are unequally shared. The other atom pulls the electrons to itself, sharing them with the hydrogen atom a smaller amount of the time. This gives the hydrogen atom a partial positive charge, causing it to be attracted to atoms with a partial negative charge. The cumulative effect of these weak bonds is life-altering, endowing water with high heat capacity, high heat of vaporization, ability to dissolve polar molecules, adhesion, cohesion, and strong surface tension.