# chem

posted by .

Po-218 is an alpha emitter with a half-life of 3.0 minutes. If a sample contains 69 mg of Po-218, how many alpha emissions would occur in 6.0 minutes?

the answer has to be _________a emmisions (which I have no idea what it means)
and I use a chart thing with amount, #H-L, and time passed as the collums.

• chem -

I would do something like this.
(Number of half lives = 6/3 = 2.)
2nn = 26/3 = 22 = 4 and
69 mg/4 = 17.25 Po atoms remain. The mass that emitted must be 69mg-17.25mg = 51.75 mg or 0.05175 grams.
I would change that to moles (moles = grams/molar mass) and remember that 1 mole of atoms contains 6.022 x 10^23 atoms.
So moles x 6.022 x 10^23 = ??number of alpha emissions.

## Similar Questions

1. ### chemistry

the half-life of polonium-218 is 3.0 minutes. what percentage of the original sample remains after 4 half-lives?
2. ### Chemistry

Po-218 is an alpha emitter with a half-life of 3.0 minutes. If a sample contains 42 mg of Po-218, how many alpha emissions would occur in 6.0 minutes?
3. ### chem

Po-218 is an alpha emitter with a half-life of 3.0 minutes. If a sample contains 56 mg of Po-218, how many alpha emissions would occur in 6.0 minutes?
4. ### trig

FInd the exact value pf the 6 trig function of alpha Given: point (-2,-6) on the terminal side of the angle in standard position sin alpha cos alpha tan alpha sec alpha csc alpha cot alpha
5. ### chemistry

A 1.50 liter gas sample at 745mm HG and 25 celsius contains 3.55% radon by volume radon-220 is an alpha emitter with a half life of 55.6 seconds. how many alpha particles are emitted in 5 minutes by this sample?
6. ### Chemistry

A 1.50- gas sample at 735 and 25.0 contains 5.00 radon-220 by volume. Radon-220 is an alpha-emitter with a half-life of 55.6 . How many alpha particles are emitted by the gas sample in 4.00 minutes?
7. ### Chemistry

A 1.50- gas sample at 722 and 25.0 contains 7.56 radon-220 by volume. Radon-220 is an alpha-emitter with a half-life of 55.6s
8. ### Chemistry

A 1.50- gas sample at 722 and 25.0 contains 7.56 radon-220 by volume. Radon-220 is an alpha-emitter with a half-life of 55.6. How many alpha particles are emitted by the gas sample in 3.00 minutes?
9. ### science

If the half-life of a 20.0g is known to be 24 minutes, how long will it take for only 5.0 grams of the sample to remain A.6 minutes B.24 minutes C.48 minutes D.96 minutes I NEED HELP!!!!
10. ### chemisty

What is the half-life of polonium-218 if 5.37 minutes are required for the activity of a sample of polonium-218 to fall to 29.5 percent of its original value?

More Similar Questions