Hydrogen fluoride - Wikipedia
WebHF is diatomic in the gas-phase. As a liquid, HF forms relatively strong hydrogen bonds, hence its relatively high boiling point. Solid HF consists of zig-zag chains of HF molecules. The HF molecules, with a short covalent H–F bond of 95 pm length, are linked to neighboring molecules by intermolecular H–F distances of 155 pm. [4] Liquid HF ...
Hydrofluoric acid - Wikipedia
WebHydrofluoric acid is a solution of hydrogen fluoride (HF) in water. Solutions of HF are colorless, acidic and highly corrosive. A common concentration is 49% (48-52%) but there are also stronger solutions (e.g. 70%) and pure HF has a …
Heart Failure | American Heart Association
WebThe American Heart Association wants to help you Rise Above Heart Failure (HF). Find out the warning signs of heart failure, also called congestive heart failure (CHF), learn about ejection fraction, and how to treat and manage your HF.
Heart failure - Symptoms and causes - Mayo Clinic
WebApr 20, 2023 · Overview. Heart failure occurs when the heart muscle doesn't pump blood as well as it should. When this happens, blood often backs up and fluid can build up in the lungs, causing shortness of breath. Certain heart conditions gradually leave the heart too weak or stiff to fill and pump blood properly.
2022 AHA/ACC/HFSA Guideline for the Management of Heart Failure
WebApr 1, 2022 · HF Description. HF is a complex clinical syndrome with symptoms and signs that result from any structural or functional impairment of ventricular filling or ejection of blood. The writing committee recognizes that asymptomatic stages with structural heart disease or cardiomyopathies are not covered under the above definition as having HF.
Hydrogen fluoride - American Chemical Society
WebJul 12, 2021 · The molecule HF is commonly called hydrogen fluoride; but its Chemical Abstracts Service name, as found in SciFinder, is hydrofluoric acid. This usage also applies to the other hydrogen halides and has the potential for confusion with the terminology for aqueous solutions of the same compounds.
Hydrogen Fluoride - Chemical Safety Facts
WebOct 14, 2022 · Hydrogen fluoride is a colorless chemical made of a hydrogen atom and a fluorine atom. When dissolved in water it is called hydrofluoric acid. As much as 60 percent of hydrogen fluoride in industrial settings is used to make refrigerants. It is used in manufacturing silicon semiconductor chips and as a catalyst in oil refineries to make high ...
Universal Definition and Classification of Heart Failure: A Step in …
WebJul 12, 2021 · Classification of HF according to LVEF now includes: HFrEF: symptomatic HF with LVEF ≤40%. HFmrEF: symptomatic HF with LVEF 41-49%. HFpEF: symptomatic HF with LVEF ≥50%. HFimpEF: symptomatic HF with a baseline LVEF ≤40%, a ≥10-point increase from baseline LVEF, and a second measurement of LVEF >40%. Language …
CDC | Facts About Hydrogen Fluoride (Hydrofluoric Acid)
WebHydrogen fluoride is a chemical compound that contains fluorine. It can exist as a colorless gas or as a fuming liquid, or it can be dissolved in water. When hydrogen fluoride is dissolved in water, it may be called hydrofluoric acid. Hydrogen fluoride can be released when other fluoride-containing compounds such as ammonium fluoride are ...
What is Heart Failure? | American Heart Association
WebMar 22, 2023 · The American Heart Association explains heart failure (HF), sometimes called congestive heart failure (CHF), as a chronic, progressive condition in which the heart muscle is unable to pump enough blood through the heart to meet the body's needs for blood and oxygen.
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