Video Experimental Relacionado
Updated: Mar 28, 2026
08:16
Ice Generation and the Heat and Mass Transfer Phenomena of Introducing Water to a Cold Bath of Brine
Published on: March 13, 2017
14.6K
Relación estadística orto-para del agua desorbida del hielo a 10 kelvin
Tetsuya Hama1, Akira Kouchi2, Naoki Watanabe2
1Institute of Low Temperature Science, Hokkaido University, Sapporo 060-0819, Japan. hama@lowtem.hokudai.ac.jp.
Science (New York, N.Y.)
|January 2, 2016
Resumen
Agua gaseosa
Área de la Ciencia:
- Astroquímica
- Física del medio interestelar
- Ciencias planetarias
Sus antecedentes:
- La relación orto-para (OPR) del agua se utiliza para inferir las temperaturas de formación de hielo en el espacio.
- Este método asume que el OPR del agua refleja su temperatura de formación de hielo en los granos de polvo.
Objetivo del estudio:
- Investigar la relación entre la relación orto-para (OPR) del agua y su temperatura de formación de hielo.
- Reevaluar el uso de OPR para determinar las temperaturas de formación de hielo interestelar.
Principales métodos:
- Formación de hielo in situ por hidrogenación de O2 a 10 grados Kelvin.
- Medición del OPR de las moléculas de agua desorbida.
Principales resultados:
- El agua desorbida del hielo de 10 Kelvin exhibió un alto OPR de 3, inconsistente con las bajas temperaturas de formación.
- Este hallazgo desafía la suposición de que el OPR del agua se correlaciona directamente con la temperatura de formación de hielo.
Conclusiones:
- La relación asumida entre el OPR del agua y la temperatura de formación de hielo es inválida.
- La reinterpretación de los OPR bajos es crucial para comprender la historia química del agua interestelar y los primeros procesos del sistema solar, incluida la formación de cometas.
Videos de Conceptos Relacionados
01:16Solubility Equilibria: Ionic Product of Water
2.1K
Pure water is a weak electrolyte; only a small amount ionizes into hydrogen and hydroxide ions. At any given temperature, the concentration of undissociated water is almost constant, so the ionic product of water is the product of the hydrogen and hydroxide ion concentrations, denoted as Kw. The square root of Kw gives the individual ion concentrations.
The ionic product of water varies with temperature, and its value is 1.0 x 10−14 at standard experimental conditions. Per Le...
The ionic product of water varies with temperature, and its value is 1.0 x 10−14 at standard experimental conditions. Per Le...
2.1K
01:14Extraction: Partition and Distribution Coefficients
5.5K
The distribution law or Nernst's distribution law is the law that governs the distribution of a solute between two immiscible solvents. This law, also known as the partition law, states that if a solute is added to the mixture of two immiscible solvents at a constant temperature, the solute is distributed between the two solvents in such a way that the ratio of solute concentrations in the solvents remains constant at equilibrium.
For extracting a solute from an aqueous phase into an...
For extracting a solute from an aqueous phase into an...
5.5K
02:41pH Scale
83.0K
Hydronium and hydroxide ions are present both in pure water and in all aqueous solutions, and their concentrations are inversely proportional as determined by the ion product of water (Kw). The concentrations of these ions in a solution are often critical determinants of the solution’s properties and the chemical behaviors of its other solutes. Two different solutions can differ in their hydronium or hydroxide ion concentrations by a million, billion, or even trillion times. A common means of...
83.0K
02:46Calculating the Equilibrium Constant
40.7K
The equilibrium constant for a reaction is calculated from the equilibrium concentrations (or pressures) of its reactants and products. If these concentrations are known, the calculation simply involves their substitution into the Kc expression.
For example, gaseous nitrogen dioxide forms dinitrogen tetroxide according to this equation:
For example, gaseous nitrogen dioxide forms dinitrogen tetroxide according to this equation:
40.7K
03:12Freezing Point Depression and Boiling Point Elevation
42.2K
Boiling Point Elevation
The boiling point of a liquid is the temperature at which its vapor pressure is equal to ambient atmospheric pressure. Since the vapor pressure of a solution is lowered due to the presence of nonvolatile solutes, it stands to reason that the solution’s boiling point will subsequently be increased. Vapor pressure increases with temperature, and so a solution will require a higher temperature than will pure solvent to achieve any given vapor pressure, including one...
The boiling point of a liquid is the temperature at which its vapor pressure is equal to ambient atmospheric pressure. Since the vapor pressure of a solution is lowered due to the presence of nonvolatile solutes, it stands to reason that the solution’s boiling point will subsequently be increased. Vapor pressure increases with temperature, and so a solution will require a higher temperature than will pure solvent to achieve any given vapor pressure, including one...
42.2K
02:30Water: A Bronsted-Lowry Acid and Base
61.5K
The reaction between a Brønsted-Lowry acid and water is called acid ionization. For example, when hydrogen fluoride dissolves in water and ionizes, protons are transferred from hydrogen fluoride molecules to water molecules, yielding hydronium ions and fluoride ions:
61.5K