Dr. Shruti Ramteke

Hello everyone, I am Dr. Shruti M Ramteke, I did my Ph.D. in chemistry. I am passionate about writing and like to share my knowledge with others . Feel free to contact me on linkedin

H2O Hybridization: Master 3 Essential Insights

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H2O hybridization

H2O’s oxygen atom undergoes sp^3 hybridization, forming 4 hybrid orbitals that accommodate 2 lone pairs and form 2 sigma bonds with hydrogen atoms. This results in a tetrahedral electronic geometry, but a bent molecular shape due to lone pair repulsion, with an observed bond angle of 104.5°, deviating from the ideal tetrahedral angle (109.5°) due to the electron pair repulsion theory.

H2O Hybridization

The hybridization of the atoms in H2O can be determined by examining the molecular geometry and electron arrangement of the molecule. In H2O, the oxygen atom is bonded to two hydrogen atoms, resulting in a bent or V-shaped molecular geometry.

H2O Hybridization

To determine the hybridization of the oxygen atom in H2O, we need to consider the electron arrangement around it. Oxygen has six valence electrons, and in H2O, four of these electrons are involved in two covalent bonds with the hydrogen atoms. The remaining two electrons are in lone pairs.

The presence of two lone pairs and two bonding pairs around the oxygen atom in H2O indicates that the oxygen atom undergoes sp3 hybridization. This means that one s orbital and three p orbitals of the oxygen atom combine to form four sp3 hybrid orbitals. The four sp3 hybrid orbitals are oriented in a tetrahedral arrangement, with two of them forming sigma bonds with the hydrogen atoms and the other two containing the lone pairs.

The hybridization of the hydrogen atoms in H2O can also be determined. Each hydrogen atom has one valence electron, which is involved in a sigma bond with the oxygen atom. Since each hydrogen atom is only bonded to one other atom and has no lone pairs, the hybridization of the hydrogen atoms is simply the s orbital.

The hybridization of the atoms in H2O can be summarized in the following table:

Atom Hybridization Orbital Type
Oxygen sp3 sp3 hybrid
Hydrogen s s orbital

The hybridization of the oxygen atom in H2O influences the molecule’s bonding and shape. The sp3 hybrid orbitals of the oxygen atom allow for the formation of sigma bonds with the hydrogen atoms and the accommodation of the lone pairs. This results in a bent or V-shaped molecular geometry, with the oxygen atom at the center.

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Molecular Geometry & Bond Angles of H2O: Uncover 5 Vital Facts

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H20 bond Angle

H2O exhibits a bent molecular geometry with a 104.5° bond angle, diverging from the ideal tetrahedral angle due to lone pair-bond pair repulsion as per VSEPR theory. Its structure, determined by sp^3 hybridization of the oxygen atom, accommodates 2 lone pairs and 2 bonding pairs, leading to a significant reduction in bond angle from the tetrahedral 109.5° to optimize electron pair repulsion minimization.

Molecular Geometry And Bond Angles of H2O

Geometry

The molecular geometry of H2O is bent or V-shaped. This is because the central oxygen atom is surrounded by two hydrogen atoms and two lone pairs of electrons. The presence of these lone pairs causes the repulsion between electron pairs, resulting in a bent shape.

H2O Molecular Geometry

Bond Angles

The bond angle in H2O is approximately 104.5 degrees. This angle is less than the ideal tetrahedral angle of 109.5 degrees due to the presence of the lone pairs on the oxygen atom. The lone pairs exert greater repulsion on the bonding pairs, pushing the hydrogen atoms closer together and resulting in a smaller bond angle.

H2O bond angle

Contribution of Bonds and Lone Pairs

The type and number of bonds, as well as the presence or absence of lone pairs on the central atom, contribute to the overall shape of the molecule. In the case of H2O:

  • The oxygen atom forms two single bonds with the two hydrogen atoms, resulting in a linear shape if there were no lone pairs. However, the presence of two lone pairs on the oxygen atom distorts the shape to a bent or V-shaped geometry.
  • The lone pairs on the oxygen atom repel the bonding pairs, causing the hydrogen atoms to move closer together and resulting in a smaller bond angle.

The following table summarizes the contributions of bonds and lone pairs to the molecular geometry and bond angles of H2O:

Central Atom Type and Number of Bonds Presence of Lone Pairs Molecular Geometry Bond Angle
Oxygen (O) Two single bonds Two lone pairs Bent or V-shaped 104.5°

Note: Lone pairs are represented by non-bonding electron pairs on the central atom.

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8+ Dehydration Synthesis Example:Detailed Explanations

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Dehydration means the removal of water molecules from anything. The addition or joining or combining of two or more molecules or compounds to form a product by removal of water molecule is known as dehydration reaction or synthesis.

Some of the various dehydration synthesis examples in chemical and biological system.

Explanation of dehydration synthesis

The term dehydration reaction is used both in chemical and biological field as from preparing ethers from alcohols in chemistry or preparing disaccharides (sucrose) in biology.  If you want to remember dehydration synthesis then you just remember the words ‘loss or lack of water’.

The dehydration reaction is also referred as condensation reaction, because in condensation reaction also there are two molecules gets condensed to form a large molecule with covalent bonds by removal of by products such as water molecule, or HCl or CH3OH or CH3COOH during the reaction. Both the dehydration and condensation are exact same processes, but water is the most frequent by product of a dehydration or condensation reaction. Let us discuss here both the examples of dehydration synthesis as from chemical field and biological field.

Dehydration synthesis examples in chemical field

ROH is the general formula for alcohols.

R=alkyl group

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Dehydration of alcohol

OH=hydroxyl group

Alcohols are characterised by the presence of hydroxyl group –OH. Alcohols are classified as primary, secondary and tertiary alcohols. The nomenclatures of alcohols are given by specifying alkyl groups containing hydroxyl group with the word alcohol. Alcohols can form alkenes by dehydration process with elimination of water. Dehydration undergoes with presence of acid and heat applied on it. Alcohol dehydration is carried out in two ways i) heating of alcohols with strong acid like sulphuric or phosphoric acid at high temperature up to 200 degree, ii) at 350-400 degree by passing the alcohol vapors on alumina (Al2O3) which is Lewis acid. The orders of reactivity of alcohol are 3°> 2°> 1°. Here are the examples of dehydration of primary, secondary and tertiary alcohols.

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Various examples of dehydration of alcohols
  • The mechanism of dehydration is as follows:
    1. In step 1 of mechanism there is the union of alcohol and hydrogen to form a protonated alcohol.
    2. In step 2 water and carbonium ion is formed with disassociation of protonated alcohol.
    3. In step 3  the alkene is formed as final product as the carbonium ion eliminates a hydrogen ion.
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Mechanism dehydration of alcohols

Similarly we can see the various examples of dehydration reaction in chemistry like as:

Etherification

R1

Etherification in which the ethers can form, by combining two same or different alcohols by using dehydration reaction.

Esterification

Esterification which involves reaction of carboxylic acid with alcohols to form ester using dehydration reaction, this reaction requires some dehydrating agents to react with water.

R5
Esterification dehydration reaction

Nitrile formation

Nitrile formation in which primary amides gets dehydrated to form nitriles.

R4
Nitrile dehydration reaction

Dehydration synthesis examples in biological field

As we already discussed above that the dehydration synthesis or reaction belongs to the formation of large molecule from the small molecules with the loss of water as by products. It is a kind of condensation reaction in which a covalent bond is formed when two functional groups are condensed (joined) with release of water molecule. In bio-system, water is the most recurrent by product of condensation reaction.

dehydration synthesis example
ATP-ADP cycle from Biologydictionary

ATP-ADP cycle

The most important example of dehydration reaction in biological field is ATP -denosine tri-phosphate and GTP-guanine tri-phosphate formation by the adding high energy phosphate bonds by condensation reaction to nucleosides like A or G i.e. adenosine or guanine, which involves the condensation reaction between adenosine di-phosphate and a phosphate group with hydrolysis of the bond.

Read more on Peptide Bond Formation:How,Why,Where,Exhaustive Facts Around It

Explanation of dehydration synthesis in biological terms:

Dehydration synthesis can be classified on the basis of the reactant, catalyst and products. present in the synthesis. Let’s we discuss about catalytic dehydration reaction. In ether formation or alkene formation the catalyst was hydrogen ion. But in biological living organism’s temperature, pH and salt concentration could not change.

Dehydration synthesis on the basis of catalyst

In living things it is important to have some catalyst to run the reversible reaction in one way. Biological catalysts are known as enzymes and their names are depends on the nature of their catalytic nature. For instance, DNA polymerase is catalytic enzymes which form DNA from deoxy-ribose nucleotides. Glycosylases is the enzyme for formation of protein from carbohydrates. The nomenclature of some enzymes is based on nature of enzyme depends on the way its catalyse the dehydration reaction. The amide bond present in between two amino acids is catalysed by ribosome (peptide bond). As the catalytic region within the ribosome is made mainly of RNA rather than protein, it is also known as an RNA enzyme or ribozyme.

Dehydration synthesis on the basis of reactants

Dehydration synthesis as per reactant used for example, carboxylic acid and amino acid are functional groups present in amino acids attached to same carbon atom. Amine group of one amino acid reacts with acid group of other amino acid which forms amide bond with the elimination of water molecule. The new amino acid formed now contain two functional groups again (dimer) i.e. amine group and carboxylic group to follow the same path of reaction with more amino acids.

Dehydration synthesis on the basis of products

Now, also dehydration reaction can be recognized from the production of its products. As we see in biological system the dehydration reaction mostly produced polymers. Rather these reactions can be recognized based on the formation of complex carbohydrate from simple monosaccharides or from acetyl acetate to produce fatty acids or form proteins from amino acids.

Lastly, the modification of biological molecules like carbohydrates, proteins and nucleosides can be done by dehydration reaction. Examples mainly include that when a carbohydrate and any molecules formed a covalent bond known as glycosidic bonds. The glycosidic bond formed among two glucose molecules when the formation of maltose from glucose is done with the elimination of water molecule. Similarly starch, glycogen or cellulose can be produced depends on position of glycosidic bond by dehydration reaction with long polymers of glucose in same way. Dehydration reaction among two monosaccharides can form other disaccharides like lactose and sucrose.

17 Facts on HCl + Na2S2O3: What, How To Balance & FAQs

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HCl Na2S2O3 300x67 1

HCl and Na2S2O3 are the chemical names of hydrochloric acid and sodium thiosulfate. Here, we are discussing the chemical reaction within HCl and Na2S2O3 compounds. Hydrochloric acid is a strong acid composed of two elements i.e. hydrogen atom and chlorine atom. Sodium thiosulphate is an inorganic salt and is composed of mainly three elements i.e. … Read more