Hydrogen Gas Evolution
Hydrogen Gas Evolution - Related Videos
06:06
Hydrogenation
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2023
Source: Vy M. Dong and Zhiwei Chen, Department of Chemistry, University of California, Irvine, CA This experiment will demonstrate the hydrogenation of chalcone as an example of an alkene hydrogenation reaction (Figure 1). In this experiment, palladium on carbon (Pd/C) will be used as a heterogeneous catalyst for the process. A balloon will be used to supply the hydrogen atmosphere. Figure 1: Diagram showing the hydrogenation of chalcone to 3-phenylpropiophenone.
08:56
Catalytic Reactor: Hydrogenation of Ethylene
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2023
Source: Kerry M. Dooley and Michael G. Benton, Department of Chemical Engineering, Louisiana State University, Baton Rouge, LA The hydrogenation of ethylene (C2H4) to ethane (C2H6) has often been studied as a model reduction reaction in characterizing new metal catalysts.1-2 While supported nickel is not the most active metal catalyst for this reaction, it is active enough that reaction can take place at < 200°C. The reaction typically involves adsorbed, dissociated hydrogen (H2) reacting...
10:23
Ideal Gas Law
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2023
Source: Laboratory of Dr. Andreas Züttel - Swiss Federal Laboratories for Materials Science and Technology The ideal gas law describes the behavior of most common gases at near-ambient conditions and the tendency of all chemical matter in the dilute limit. It is a fundamental relationship between three measurable macroscopic system variables (pressure, temperature, and volume) and the number of molecules of gas in the system, and is therefore an essential link between the microscopic and the...
12:02
Molecular Evolution of the Tre Recombinase
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Cited by 4 •
2008
Here we report the generation of Tre recombinase through directed, molecular evolution. Tre recombinase recognizes a pre-defined target sequence within the LTR sequences of the HIV-1 provirus, resulting in the excision and eradication of the provirus from infected human cells. While still in its infancy, directed molecular evolution will allow the creation of custom enzymes that will serve as tools of molecular surgery and molecular medicine.
06:32
A Simple, Low-cost, and Robust System to Measure the Volume of Hydrogen Evolved by Chemical Reactions with Aqueous Solutions
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Cited by 15 •
2016
The study of methods to generate on-demand hydrogen for fuel cells continues to grow in importance. However, systems to measure hydrogen evolution from the reaction of chemicals with water can be complicated and expensive. This article details a simple, low-cost, and robust method to measure the evolution of hydrogen gas.
FAQs
At the reactive surface, the decisive step is electron transfer to either protons or water molecules. This reduction produces hydrogen atoms at the surface, and neighboring atoms then combine into molecular H₂. Gas does not necessarily appear immediately: bubbles form only after dissolved hydrogen makes the solution supersaturated, linking the visible endpoint to both reaction rate and gas accumulation over time.
Electrode material, applied potential, electrolyte composition, and temperature act as key variables because they influence how rapidly hydrogen-forming electron-transfer steps proceed. Changing one condition can therefore alter the observed evolution rate without changing the overall hydrogen product. Studying these variables helps evaluate how the reactive surface and surrounding solution affect the efficiency of hydrogen formation.
Hydrogen evolution can be examined in several chemical settings, but the source of the reducing electrons differs. In metal-acid reactions, a reactive metal and acid participate; in electrolysis, an applied electrical input drives the process; electrocatalysis focuses on how an electrode promotes it. Comparing these settings reveals how reactants, electrical conditions, and surfaces shape hydrogen production.
Bubble formation provides a visible consequence of reduction at a reactive surface, so it can indicate that electron transfer is occurring. However, the timing and amount of bubbling also depend on supersaturation, electrode material, applied potential, electrolyte composition, and temperature. For that reason, bubbles are useful observational evidence, while controlled conditions are needed for meaningful comparison.
A controlled study should specify whether hydrogen is generated through a metal-acid reaction, electrolysis, or electrocatalysis, then record electrode material, applied potential when relevant, electrolyte composition, and temperature. Observing the onset and rate of gas evolution under defined conditions allows comparisons among experiments and supports quantitative analysis without treating every difference in bubbling as a change in reaction identity.
Hydrogen evolution supports corrosion analysis because it connects surface reactivity with a measurable redox-related outcome. Investigators can examine whether gas forms and how its evolution rate changes as the reactive surface, electrolyte composition, or temperature changes. This approach helps relate corrosion behavior to chemical conditions, while avoiding conclusions based solely on bubble visibility when supersaturation controls their appearance.
Efficient renewable hydrogen generation depends on controlling the factors that influence the evolution rate, particularly electrode material, applied potential, electrolyte composition, and temperature. Electrocatalysis is relevant because it examines how electrode surfaces promote hydrogen formation. Understanding these relationships helps guide the development of systems that produce hydrogen more effectively under selected chemical and electrical conditions.
Experiments can provide evidence that reduction is occurring, show when bubbles begin to emerge, and allow the evolution rate to be compared across conditions. These outcomes are useful in quantitative experiments because gas formation responds to electrode material, applied potential, electrolyte composition, and temperature. Interpreting the results requires recognizing that visible bubbling begins only after supersaturation is reached.