The graph below shows the decay for a sample of 400g of iodine -131. Study is and answer question that follow.

The graph below shows the decay for a sample of 400g of iodine -131. Study is and
answer question that follow.

(i) Use the graph to determine the half-life of the sample
(ii) What fraction of the original sample remains after 16.2 days.

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(i) 8.1 from the graph
(ii)Reading mass after 16.2days from graph = 100g
100/400 = ¼

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sharon kalunda answered the question on May 16, 2019 at 11:33

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