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If you start with 7,152 grams of a radioactive kind of lanthanum and the half-life is 93 minutes, how much will be left after 186 minutes

User Flowera
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1 Answer

6 votes

Answer:

1788 grams

Explanation:

If you start with 7,152 grams of a radioactive kind of lanthanum and the half-life is 93 minutes, how much will be left after 186 minutes

We are to find Nt

The formula is given as:

Nt = No(1/2)^t/t½

Where

No = Initial amount = 7,152 grams

t = time elapsed = 186 minutes

t½ = Half life = 93 minutes

Nt = Amount of substance left

Nt = 7152(1/2)^186/93

= 1788 grams

User Steve Peak
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