chemical compound: Quick Facts

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Two diagrams show the three-dimensional structure of a methane molecule: panel A uses a ball-and-stick model with a central carbon atom connected to four hydrogen atoms in a tetrahedral arrangement, while panel B illustrates the bond angle of 109.5 degrees and bond length of 1.09 angstroms between carbon and hydrogen atoms.

Diagram showing the formation of a polar covalent bond in a water molecule, with two hydrogen atoms bonding to one oxygen atom to form H2O, illustrating shared electrons and chemical reaction.

A metal pipette pours shiny liquid mercury onto a smooth surface, forming a large reflective puddle surrounded by smaller, round droplets.

A color-coded periodic table of the elements displays each element's symbol and atomic number, with categories such as alkali metals, noble gases, halogens, transition metals, and actinoid elements distinguished by different background colors.

A simplified periodic table highlights metals in pink, nonmetals in blue, and metalloids in green, showing their distinct regions and groupings within the table.

Line graph showing the first ionization energies of the elements as a function of atomic number, with peaks at noble gases like helium, neon, argon, krypton, xenon, and radon, and labeled elements at key points.

A periodic table chart displays the electronegativity values for each element, with values increasing from left to right and decreasing from top to bottom, highlighting how strongly atoms attract shared electrons.

Diagram showing the formation of an ionic bond between sodium (Na) and chlorine (Cl) atoms. Sodium loses an electron to become Na+, chlorine gains an electron to become Cl-, resulting in sodium chloride (NaCl), or table salt.

Diagram of a diborane molecule showing a three-center, two-electron bond where two boron atoms and a central hydrogen atom are connected by overlapping orbitals, with a pair of electrons shared among all three atoms.

structural formulas of some organic compounds

Investigate the magnetlike ionic bond formed when electrons transfer from one atom to another

See molecular bonds at work as two hydrogen atoms join a sulfur atom to make hydrogen sulfide

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Topics

chemical bonding chemical analysis coordination compound organic compound organometallic compound chemical reaction inorganic compound polymer ionic compound What is Hexavalent Chromium (or Chromium-6)?chemical element phase molecule radiation subatomic particle atom electricity liquid time light

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Key People

Portrait of French chemist Antoine Laurent Lavoisier, shown in formal 18th-century attire with a white wig and ruffled cravat, looking slightly to his left.

Antoine Lavoisier

French chemist

Guyton de Morveau, Louis Bernard

Louis Bernard Guyton de Morveau

French chemist and educator

German Swedish chemist Carl Wilhelm Scheele, c. 1780.

Carl Wilhelm Scheele

Swedish chemist

Martin Heinrich Klaproth, engraving

Martin Heinrich Klaproth

German chemist

Vauquelin, lithograph by François-Séraphin Delpech

Nicolas-Louis Vauquelin

French chemist

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Edmond Frémy

French chemist

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Georg Brandt

Swedish chemist

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Carl Wagner

German chemist and metallurgist

Periodic Table of the elements concept image (chemistry)

Facts You Should Know: The Periodic Table Quiz

A person's hand pouring blue fluid from a flask into a beaker. Chemistry, scientific experiments, science experiments, science demonstrations, scientific demonstrations.

Ins and Outs of Chemistry

Double exposure of science laboratory test tubes with bokeh and chemical reaction

Types of Chemical Reactions