Chlorate (ClO3 − ) is a toxic anion in polluted water from the use of high energy materials, herbicide, and drinking water disinfection with chlorine chemicals. In a reaction for the catalytic reduction of ClO3 − into the non-toxic chloride (Cl− ), the reaction rate constant was measured as 9.98 hr−1 , then how many minutes does the reaction take to reduce 90% of the chlorate in the water?