acceleration of a chemical reaction induced the presence of material that is chemically unchanged at the end of the reaction; "of the top 50 commodity chemicals, 30 are created directly by catalysis and another 6 are made from raw materials that are catalytically produced"
a tentative theory about the natural world; a concept that is not yet verified but that if true would explain certain facts or phenomena; "a scientific hypothesis that survives experimental testing becomes a scientific theory"; "he proposed a fresh theory of alkalis that later was accepted in chemical practices"
a proposal intended to explain certain facts or observations
sturdy and strong in constitution or construction; enduring; "a rugged trapper who spent months in the wilderness"; "those that survive are stalwart rugged men"; "with a house full of boys you have to have rugged furniture"
very difficult; severely testing stamina or resolution; "a rugged competitive examination"; "the rugged conditions of frontier life"; "the competition was tough"; "it's a tough life"; "it was a tough job"
having great power or force or potency or effect; "the most powerful government in western Europe"; "his powerful arms"; "a powerful bomb"; "the horse's powerful kick"; "powerful drugs"; "a powerful argument"
characterized by or full of force or strength (often but not necessarily physical); "a forceful speaker"; "a forceful personality"; "forceful measures"; "a forceful plan for peace"