Hydrate Analysis
Hydrate Analysis - Related Videos
01:24
Hydration of Cement
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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...
02:42
Aqueous Solutions and Heats of Hydration
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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...
09:48
In Situ Characterization of Hydrated Proteins in Water by SALVI and ToF-SIMS
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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.
01:29
Strength and Heat of Hydration
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2024
The hydration of cement is an exothermic reaction in which heat is generated as cement hydrates. This heat of hydration is critical to cement's strength development. The rate at which this heat is generated affects the temperature rise, with a majority of the heat being released early in the hydration process, half within the first three days, and about 75% within the first week. The heat of hydration for each cement compound is significant; for instance, tricalcium aluminate (C3A) and...
09:59
Preparation of Primary Neurons for Visualizing Neurites in a Frozen-hydrated State Using Cryo-Electron Tomography
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Cited by 24 •
2014
To preserve neuronal processes for ultrastructural analysis, we describe a protocol for plating of primary neurons on electron microscopy grids followed by flash freezing, yielding samples suspended in a layer of vitreous ice. These samples can be examined with a cryo-electron microscope to visualize structures at the nanometer scale.
FAQs
The key calculation uses the mass lost during heating, not the original hydrate mass alone. That loss represents water of crystallization; converting it to moles and comparing it with the moles of remaining anhydrous compound gives the simplest water-to-compound ratio. This ratio supplies the subscript used in the hydrate’s empirical formula.
Constant mass indicates that repeated heating no longer produces a measurable additional loss. This condition supports the conclusion that the water removed during the procedure has been accounted for before the mole ratio is calculated. Stopping earlier could leave residual water in the solid and distort the inferred hydrate formula.
Hydrate analysis separates the compound into two stoichiometric contributions: water released from the crystal and the anhydrous material left after heating. The measured mass loss is assigned to water, while the final mass is used for the anhydrous compound. Comparing their mole amounts reveals how many water units correspond to each compound unit.
Temperature provides the driving condition for removing water of crystallization and can also reveal how a crystalline material changes as it is heated. The measured outcome depends on identifying the mass after water removal rather than treating every temperature-related mass change as a new compound. This makes controlled heating and stable weighing essential for interpretation.
A weighed hydrate is heated to remove its crystallization water, then cooled and weighed again. Heating and cooling are repeated until the measured mass becomes constant. The initial mass, final mass, and resulting mass difference are then used to calculate water lost, moles of water, moles of anhydrous compound, and the empirical formula.
Together, the final mass and mass loss provide more than a simple change in sample size. The final mass represents the anhydrous compound for mole calculations, while the difference estimates the water content. Their ratio can support compound identification, establish an empirical formula, and provide a basis for stoichiometric calculations.
The method is useful when a crystalline compound must be characterized through its water content. Its results can help identify a hydrate, assess whether its composition matches an expected formula, and evaluate purity through stoichiometric comparison. Because heating changes the crystal composition, the procedure also supports investigations of temperature-related behavior in crystalline materials.