DDT on exposure to water decomposes. How much time will it take for its 90% decomposition? (Half-life = 20 years)

D D T an exposure to water decomposes. Half life = 10 years. How much time will it take for its 99% decomposition?50 years, 66.5 years, 500 years, 700 years

DDT on exposure to water decomposes according to first order kinetics. Half life = 10 years. How much time it will take for its decomposition to 99%?

Thermal decomposition of a compound is of first order. If 50% of the compound is decomposed in 120 minute, how much time it take for the 90% decomposition of the compound ?

A first order reaction taken 32 minutes for 50% completion. Hew much time will it take for 90% completion ?

90% of a first order reaction was completed in 100 min . How much time it will take for 80% completion of a reaction

90% of a first order reaction was completed in 100 min . How much time it will take for 80% completion of a reaction

80% of a fisrt order reaction was completed in 70 min . How much it will take for 90% completion of a reaction?