A compound containing polar hydroxyl groups along the hydrocarbon chain Animation Play

A covalent bond between the same atoms Animation Play

A double bond Animation Play

A model of a morphine molecule Illustration Play

A proof for rapid exchange of hydrogen atoms in hydroxyl groups Slideshow Play

Abiotic factors Slideshow Play

About the experiment Whiteboard exercise Play

Abundance of chemical elements in nature Student activity Play

Abundance of elements in nature Slideshow Play

Abundance of noble gases in the atmosphere Slideshow Play

Abundance of the elements in the crust and in the whole Earth Animation Play

Acid dissociation constant and pH (1) Student activity Play

Acid dissociation constant for lactic acid Animation Play

Acid rain Student activity Play

Acidic properties Student activity Play

Acids (1) Student activity Play

Adaptations of plants to life on land Student activity Play

Additional information contained in chemical equations Student activity Play

Aerobic respiration Student activity Play

Aerobic respiration Slideshow Play

Aerobic respiration Animation Play

Air Class activity Play

Air Whiteboard presentation Play

Air and the atmosphere Student activity Play

Air pollution with nitrogen monoxide Slideshow Play