Henry Taube, who won a Nobel Prize in Chemistry for describing how electrons hop between molecules during chemical reactions, died on Wednesday at his home on the campus of Stanford University, where he had taught for two decades. He was 89.

Stanford announced his death yesterday.

Dr. Taube studied reactions in which some molecules grab electrons from other molecules. These reactions -- known as redox, a contraction of ''reduction'' and ''oxidation,'' which chemists use to define this give and take of electrons -- occur widely, in engine combustion, plant photosynthesis and animal respiration, for example.

''He developed organizing principles for thinking about how these chemical changes occurred,'' said John Brauman, a professor of chemistry at Stanford, where Dr. Taube (the first syllable rhymes with ''how'') worked as a professor from 1961 to 1986, when he retired. He continued his experimental work until recently, the university said.

''He laid out a whole way of thinking about things,'' Dr. Brauman said. ''His knowledge of experimental chemistry was superb, and the experiments he carried out were spectacularly good.''

In experiments looking at chemical reactions in metallic solutions, Dr. Taube found that electrically charged atoms, known as ions, had to form, in essence, a chemical bridge before electrons could move between them. Previously, scientists thought these reactions simply involved the transfer of electrons.

The discovery helped explain why reactions among similar kinds of metals and ions occurred at speeds very quickly -- why gunpowder explodes when heated by a match, for example -- while others occurred slowly.

The work even helps explain why people do not spontaneously combust. James P. Collman, another of Dr. Taube's colleagues at Stanford, said fats and proteins are oxidizing molecules, prone to losing electrons. Oxygen tends to gain electrons, so the flesh and oxygen should combine and release energy -- burn, in other words. ''You are not stable,'' Dr. Collman said. ''But oxygen is very slow in its reactions.''

Dr. Collman helped explain why some redox reactions occurred quickly and others happened so slowly that they were imperceptible. He also showed, through experiments and theoretical work, how the addition of metals like ruthenium could greatly speed the slow redox reactions.

Born in Neudorf, Saskatchewan, Henry Taube, a son of immigrant farmers from Russia, obtained his bachelor's and master's degrees at the University of Saskatchewan and then completed his doctoral degree at the University of California, Berkeley, in 1940.

He taught at Cornell and the University of Chicago before joining Stanford. He served twice as chairman of its chemistry department.

He became a naturalized American citizen in 1942. ''He always described himself as farm boy who wandered into where he was now,'' Dr. Collman said.

In 1983, the Swedish Academy of Sciences awarded Dr. Taube the Nobel Prize for ''his work in the mechanisms of electron transfer reactions, especially in metal complexes.''

Dr. Taube was a member of the National Academy of Sciences and received a National Medal of Science in 1977.

He is survived by his wife of 53 years, Mary; his sons Karl, of Riverside, Calif., and Heinrich, of Chicago; a daughter, Linda Taube of Galway, Ireland; and five grandchildren. A stepdaughter, Marianna Taube, died in 1998.

Photo: Henry Taube in undated photo. (Photo by Chuck Painter/Stanford News Service, via Associated Press)