Radon-22 has a half life of 4 days. If you begin with 32 grams of radon, how many grams will be left after 20 days?

20 days is 5 half-lives.

Divide 32 by two, five times.

That is the same as dividing 32 by 2^5.

thank you drwls for the help

To calculate how many grams of radon will be left after 20 days, you can use the formula for calculating exponential decay:

N(t) = N₀ * (1/2)^(t / T)

Where:
N(t) is the amount of radon remaining after time t
N₀ is the initial amount of radon (32 grams in this case)
t is the time elapsed (20 days)
T is the half-life of radon-22 (4 days)

Let's substitute the given values into the formula:

N(20) = 32 * (1/2)^(20 / 4)

Now, we can solve this equation to find the amount of radon remaining after 20 days.

N(20) = 32 * (1/2)^5
N(20) = 32 * 1/32
N(20) = 1 gram

Therefore, after 20 days, there will be approximately 1 gram of radon remaining.