Diseases, Conditions, Syndromes

Taming COVID-19 requires urgent search for both vaccine and treatment

Bonnie Robeson, a senior lecturer at the Johns Hopkins Carey Business School, knows what it's like to take part in an urgent race to find a vaccine or treatment for a lethal malady, such as the current effort to contain the ...

Medical research

Researchers discover new compound that promotes lung health

A molecule identified by UCLA researchers helps maintain a healthy balance of cells in airway and lung tissue. If the compound, so far only studied in isolated human and mouse cells, has the same effect in people, it may ...

Genetics

Scientists link rapid brain growth in autism to DNA damage

Researchers at the Salk Institute have discovered a unique pattern of DNA damage that arises in brain cells derived from individuals with a macrocephalic form of autism spectrum disorder (ASD). The observation, published ...

Oncology & Cancer

Inhibition of p38 reduces the growth of lung tumors

One of the biggest challenges faced by biomedicine is the development of more selective and efficient cancer treatments. In 2018, 1.7 million people died from lung cancer worldwide, a number equivalent to the population of ...

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Chemical compound

A chemical compound is a pure chemical substance consisting of two or more different chemical elements that can be separated into simpler substances by chemical reactions and that have a unique and defined chemical structure. Chemical compounds consist of a fixed ratio of atoms that are held together in a defined spatial arrangement by chemical bonds. Chemical compounds can be compound molecules held together by covalent bonds, salts held together by ionic bonds, metallic compounds held together by metallic bonds, or complexes held together by coordinate covalent bonds. Substances such as pure chemical elements and elemental molecules consisting of multiple atoms of a single element (such as H2, S8, etc.) are not considered chemical compounds.

Elements form compounds to become more stable. They become stable when they have the maximum number of possible electrons in their outermost energy level, which is normally two or eight valence electrons. This is the reason that noble gases do not frequently react: they already possess eight valence electrons (the exception being helium, which requires only two valence electrons to achieve stability).

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