A radioactive element has a half-life of six days then the approximate decay rate of the element after the first day is 8.3%.
Half life time is that time during which half of the concentration of reactant will changed into the product.
According to the question:
In 6 days = 50% of the reactant will change into product
In 1 day = 50%/6 of the reactant will change into product
So, in 1 day = 8.3% of the reactant will change into product
Hence option (3) is correct.
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