Hydrate Ion Size
Hydrate Ion Size - Related Videos
02:54
Trends in Lattice Energy: Ion Size and Charge
0 Views •
2020
An ionic compound is stable because of the electrostatic attraction between its positive and negative ions. The lattice energy of a compound is a measure of the strength of this attraction. The lattice energy (ΔHlattice) of an ionic compound is defined as the energy required to separate one mole of the solid into its component gaseous ions. For the ionic solid sodium chloride, the lattice energy is the enthalpy change of the process: Conventions Here, the convention is used where the ionic...
02:42
Aqueous Solutions and Heats of Hydration
0 Views •
2020
Water and other polar molecules are attracted to ions. The electrostatic attraction between an ion and a molecule with a dipole is called an ion-dipole attraction. These attractions play an important role in the dissolution of ionic compounds in water. When ionic compounds dissolve in water, the ions in the solid separate and disperse uniformly throughout the solution because water molecules surround and solvate the ions, reducing the strong electrostatic forces between them. This process...
01:24
Hydration of Cement
0 Views •
2024
Hydration of cement is a chemical reaction between cement particles and water. This process occurs primarily through two mechanisms: through-solution and topochemical. In the through-solution process, anhydrous compounds dissolve into their constituents, hydrates form in the solution, and then precipitate from the supersaturated solution. The topochemical process involves solid-state reactions at the cement particle surface. The through-solution process dominates the topochemical process at the...
09:48
In Situ Characterization of Hydrated Proteins in Water by SALVI and ToF-SIMS
0 Views •
Cited by 13 •
2016
This work presents a protocol for liquid handling and sample introduction to a microchannel for in situ time-of-flight secondary ion mass spectrometry analysis of protein biomolecules in an aqueous solution.
02:54
Ions as Acids and Bases
0 Views •
2020
Salts with Acidic Ions Salts are ionic compounds composed of cations and anions, either of which may be capable of undergoing an acid or base ionization reaction with water. Aqueous salt solutions, therefore, may be acidic, basic, or neutral, depending on the relative acid-base strengths of the salt’s constituent ions. For example, dissolving the ammonium chloride in water results in its dissociation, as described by the equation: The ammonium ion is the conjugate acid of the base ammonia,...
FAQs
The decisive factor is charge density, which increases when substantial charge is concentrated within a small ionic radius. A stronger electric field then attracts and organizes surrounding water molecules more tightly, producing a more strongly bound hydration shell. Consequently, the ion can behave as a larger solvated species even when its bare ionic radius is relatively small.
Bare ionic radius describes the ion itself, whereas hydrated ion size reflects the ion together with water molecules that move with it. These measures can therefore rank ions differently. An ion with a smaller bare radius may interact more strongly with water and act as a larger effective species in solution, so bare size alone may not predict transport behavior.
Ionic charge, radius, and charge density are the principal variables identified for hydration-shell strength. Increasing charge or reducing radius generally raises charge density and strengthens the interaction with surrounding water. The resulting change in hydration influences the effective species size, helping explain why ions with similar bare dimensions can show different behavior during movement through solution.
Effective size affects how readily an ion moves through solution, because transport reflects the ion and the water associated with it rather than the bare ion alone. Differences in hydration can therefore contribute to contrasting ionic mobilities and electrical conductivities. Interpreting conductivity alongside hydrated size provides a more chemically meaningful view of how ions travel in solution.
For diffusion and membrane transport, the relevant species may include an ion’s associated hydration shell. Stronger hydration can make the effective species behave as larger, which helps account for differences in transport through membranes or ion-exchange materials. This perspective supports comparisons among ions when their bare ionic radii do not adequately explain observed movement.
Hydrated ion size is useful when interpreting or designing separation, electrochemical, and environmental chemistry processes. In separations and ion-exchange systems, effective ionic dimensions help contextualize how ions move through a material. In electrochemical and environmental studies, the concept connects ion hydration with conductivity, diffusion, and transport behavior in solution.