Key PointsHydrogen bonds are strong intermolecular forces developed when a hydrogen atom external inspection to one electronegative atom ideologies a surrounding electronegative atom.Greater electronegativity the the hydrogen link acceptor will certainly lead to rise in hydrogen-bond strength.The hydrogen bond is among the strongest intermolecular attractions, but weaker than a covalent or one ionic bond.Hydrogen bonds are responsible because that holding together DNA, proteins, and also other macromolecules.

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Termshydrogen bondThe attraction between a partly positively fee hydrogen atom attached come a highly electronegative atom (such together nitrogen, oxygen, or fluorine) and also another surrounding electronegative atom.electronegativityThe propensity of an atom or molecule to attract electrons in the direction of itself, form dipoles, and also thus kind bonds.intermolecularA kind of interaction in between two different molecules.

Forming a Hydrogen Bond

A hydrogen link is the electromagnetic attraction created between a partially positively charged hydrogen atom attached to a extremely electronegative atom and another adjacent electronegative atom. A hydrogen link is a type of dipole-dipole interaction; it is no a true chemistry bond. These attractions deserve to occur between molecules (intermolecularly) or within different parts that a solitary molecule (intramolecularly).

Hydrogen bonding in waterThis is a space-filling round diagram the the interactions between separate water molecules.

Hydrogen bond Donor

A hydrogen atom attached to a fairly electronegative atom is a hydrogen bond donor. This electronegative atom is commonly fluorine, oxygen, or nitrogen. The electronegative atom attractive the electron cloud from roughly the hydrogen cell core and, by decentralizing the cloud, leaves the hydrogen atom through a hopeful partial charge. Since of the small size of hydrogen loved one to other atoms and molecules, the resulting charge, though just partial, is stronger. In the molecule ethanol, there is one hydrogen atom bonded to one oxygen atom, which is an extremely electronegative. This hydrogen atom is a hydrogen link donor.

Hydrogen shortcut Acceptor

A hydrogen shortcut results as soon as this solid partial hopeful charge attracts a lone pair of electron on another atom, which i do not care the hydrogen bond acceptor. One electronegative atom such together fluorine, oxygen, or nitrogen is a hydrogen bond acceptor, regardless of whether it is external inspection to a hydrogen atom or not. Higher electronegativity the the hydrogen bond agree will create a more powerful hydrogen bond. The diethyl ether molecule consists of an oxygen atom that is not bonded to a hydrogen atom, making the a hydrogen link acceptor.

Hydrogen link donor and hydrogen shortcut acceptorEthanol contains a hydrogen atom the is a hydrogen bond donor since it is external inspection to one electronegative oxygen atom, i m sorry is very electronegative, so the hydrogen atom is slightly positive. Diethyl ether contains an oxygen atom that is a hydrogen link acceptor since it is no bonded to a hydrogen atom and also so is slightly negative.

A hydrogen attached come carbon can likewise participate in hydrogen bonding as soon as the carbon atom is bound come electronegative atoms, as is the case in chloroform (CHCl3). Together in a molecule where a hydrogen is attached to nitrogen, oxygen, or fluorine, the electronegative atom attracts the electron cloud from around the hydrogen cell nucleus and, by decentralizing the cloud, leaves the hydrogen atom v a confident partial charge.

Interactive: Hydrogen BondingExplore hydrogen binding forming in between polar molecules, such as water. Hydrogen bonds are shown with dotted lines. Show partial charges and run the model. Where perform hydrogen bond form? Try an altering the temperature that the model. Just how does the pattern of hydrogen bonding explain the lattice that provides up ice crystals?

Applications for Hydrogen Bonds

Hydrogen bonds happen in inorganic molecules, such together water, and organic molecules, such together DNA and also proteins. The two complementary strands the DNA are hosted together through hydrogen bonds between complementary nucleotides (A&T, C&G). Hydrogen bonding in water contributes come its distinctive properties, consisting of its high boiling allude (100 °C) and surface tension.

Water droplets top top a leafThe hydrogen binding formed in between water molecules in water droplets space stronger 보다 the other intermolecular forces between the water molecules and also the leaf, contributing come high surface tension and also distinct water droplets.

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In biology, intramolecular hydrogen bonding is partly responsible for the secondary, tertiary, and quaternary structures of proteins and also nucleic acids. The hydrogen bonds help the proteins and nucleic acids kind and maintain particular shapes.

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