Question

The half-life of radium is 1690 years. If 80 grams are present now, how much will be present in 160 years?

grams
(Do not round until the final answer. Then round to the nearest thousandth as needed.)
Need help thanks

Answer 1

Answer: 74.919 grams

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Step-by-step explanation:

One half-life formula we can use is

y = P*(0.5)^(x/H)

where,

• x = number of years = 160
• y = amount present after x years = unknown for now
• H = half-life = 1690 years
• P = starting amount = 80 grams

So,

y = P*(0.5)^(x/H)

y = 80*(0.5)^(160/1690)

y = 74.9186780773447

y = 74.919

There are roughly 74.919 grams of radium leftover.