Higher energy means shorter bonds which means stronger bonds. Branched alkane hydrocarbons are thermodynamically more stable than straight-chain linear alkanes. This thermodynamic stability is also manifest in alkane bond separation energies. Solution : Out of the given four alkenes, alkene B is the most stable alkene. For example, if equal quantities of two isomeric hydrocarbons burn to produce equal amounts of carbon dioxide and water, the one releasing more energy i. The linear polysaccharides with highly regular conformation that can form crystalline or partial crystalline structures are mostly insoluble in water, while branching structure could increase the solubility for two reasons: 1 the branching structure could weaken the intramolecular interaction due to the steric ….
The boiling point of a liquid depends on temperature, atmospheric pressure, and the vapor pressure of the liquid. Secondary carbocations will require more energy than tertiary, and primary carbocations will require the most energy. The linear polysaccharides with highly regular conformation that can form crystalline or partial crystalline structures are mostly insoluble in water, while branching structure could increase the solubility for two reasons: 1 the branching structure could weaken the intramolecular interaction due to the steric.
So, the melting point depends on the energy it takes to overcome the forces between the molecules, or the intermolecular forces, holding them in the lattice.
The stronger the intermolecular forces are, the more energy is required, so the higher the melting point is. Alkanes are saturated hydrocarbons. This means that their carbon atoms are joined to each other by single bonds. This makes them relatively unreactive, apart from their reaction with oxygen in the air — which we call burning or combustion.
SeniorCare2Share Care about seniors? Have knowledge? Care to share? Table of Contents. The branching, it seems, means that the electronic structure is simply more compact and this decreases molecular surface area per atom and so leads to a lowering of energy and a concomitant increase in stability. Straight chain compounds have large size and hence have large polarizability and have strong London dispersion forces hence high boiling points while branched compounds have compact structure and hence have low polarizability and have low boiling points.
Because alkane molecules are nonpolar , they are insoluble in water, which is a polar solvent, but are soluble in nonpolar and slightly polar solvents.
Consequently, alkanes themselves are commonly used as solvents for organic substances of low polarity, such as fats, oils, and waxes. Due to branching the surface area of molecules decreases which makes it more compact, it will be easier to pack them tightly and it will be hard to break that compact structure so this explains that due to branching the melting point increases. Branching decreases the boiling point Van der Waals dispersion force is proportional to the surface area.
Branching in molecules decreases the surface area thereby decreasing the attractive force between individual molecules. As a result, the boiling point decreases. The linear polysaccharides with highly regular conformation that can form crystalline or partial crystalline structures are mostly insoluble in water, while branching structure could increase the solubility for two reasons: 1 the branching structure could weaken the intramolecular interaction due to the steric These four bonds formed by carbon in alkanes are sigma bonds, which are more stable than other types of bond because of the greater overlap of carbon's atomic orbitals with neighboring atoms' atomic orbitals.
To make alkanes react, the input of additional energy is needed; either through heat or radiation. Within the carbocations, a tertiary carbocation is more stable than a secondary one which in turn is more stable than a primary one.
So the tert-butyl cation is more stable than the propanyl one — but remember that both are still very reactive. Tetra-substituted alkene is the most stable followed by tri-substituted and di-substituted and then mono-substituted. Alkenes have substituents, hydrogen atoms attached to the carbons in the double bonds. The branching, it seems, means that the electronic structure is simply more compact and this decreases molecular surface area per atom and so leads to a lowering of energy and a concomitant increase in stability.
The team carried out the necessary geometry optimizations and harmonic frequency computations using the Gaussian program, they calculated molecular surface area using Chimera and harmonic frequencies in GAMESS.
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