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100 mg

= 50 mg after 1 hl

= 25 mg after 2 hl

= 12.5 mg after 3 hl

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14y ago
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AnswerBot

5mo ago

After 3 half-lives, the remaining mass is ( \frac{1}{8} ) of the original mass. So if the original mass is 12.5 mg, the final mass after 3 half-lives would be ( 12.5 , \text{mg} \times \frac{1}{8} = 1.56 , \text{mg} ).

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Q: What is the original mass of 12.5 mg after 3 half lives?
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Continue Learning about Natural Sciences

How many half lives have elapsed to yield a sample with 125 atoms of C-14?

We have now way of knowing unless we know the initial number of C-14


If a sample contains 100g of a radioactive isotope how much will be left after 3 half lives?

There will be 125 grams of radium left. Keep it simple. Ih a half-life, half the sample decays. Half of 1000 grams is 500 grams, then half of 500 grams is 250 grams. Half of that again is 125 grams. And just so you know, the half-life of radium-226, the non-synthetic isotope of radium, is 1602 years. If this was the case here, 4806 years would have to pass to get the sample to decay as far as it did.The remained quantity of radium after 3 x 1602 years is 125 grams.


What is the atomic mass for 125 pounds?

The atomic mass is a property that refers to the average mass of an atom of an element. It is measured in atomic mass units (amu) or grams per mole. The atomic mass is not directly related to pounds, which is a unit of weight in the imperial system.


Do all isotopes have the same half lives?

Yes, all elements have at least one radioactive isotope. Hydrogen has two isotopes, Deuterium and Tritium. H3 has a half life of 12.3 years. Not all isotopes are radioactive. About half way up the atomic mass table, Tin appears to have the greatest number of stable isotopes - ten out of about 124 isotopes in all.


Calculate the density of a substance that has a mass of 125 grams and a volume of 170 ml?

Density = mass/volume Density = 125 g / 170 ml Density ≈ 0.74 g/ml

Related questions

How many half-lives have elapsed to yield a sample with 125 atoms of C-14 and 375 atoms of N-14?

To determine the number of half-lives that have elapsed, we first find the total number of atoms in the sample, which is 500 (125 + 375). The starting atom would have been from 250 atoms of C-14. To find the number of half-lives elapsed, we divide the total number of atoms by the starting amount (500/250). This gives us 2 half-lives that have elapsed.


How many grams of sodium-24 will remain at the end of 4 half-lives?

At the end of 4 half-lives, only 1/16th (1/2^4) of the original amount of sodium-24 will remain. If you start with 100 grams, at the end of 4 half-lives, you will have 6.25 grams remaining (100 grams * 1/2^4).


What is half of 250?

125


What is the half number between 125 and 250?

The number half-way between 125 and 150 is (125 + 250) / 2 = 187.5.


The halflife of Na24 is 15 hours When there are 1000 atoms of Na24 in a sample a scientist starts a stopwatch The scientist stops the stopwatch at 45 hours there are atoms of Na24 rema?

There will be 125 atoms of Na24 remaining in the sample after 45 hours. This calculation is based on the fact that after 3 half-lives (45 hours/15 hours per half-life), the original 1000 atoms would have reduced by a factor of 2 three times, resulting in 1000/2/2/2 = 125 atoms remaining.


Half of 250 is 125?

Yes, half of 250 is 125. To prove it: use a calculator and calculate 125 times 2.


Are 125 grams and 125 centimeters the same?

No, a gram is a unit of mass (125 grams is about 4.4 ounces[mass]). A centimeter is a unit of length (125 cm is about 49 inches long).


The half-life of Na-24 is 15 hours When there are 1000 atoms of Na-24 in a sample a scientist starts a stopwatch The scientist stops the stopwatch at 45 hours there are atoms of Na-24 remaining?

Based on the half-life of Na-24, after 1 half-life (15 hours), there would be 500 atoms remaining. After 2 half-lives (30 hours), there would be 250 atoms remaining. After 3 half-lives (45 hours), there would be 125 atoms remaining in the sample.


What is the percent of change from 125 to 135?

percent of change from 125 to 135 = 8%% change =|original value - new value|/original value * 100%= |125 - 135|/125 * 100%= 10/125 * 100%= 0.08 * 100%= 8%


What is The Half of 125?

62.5


What is original price of an item if a discount of 20 percent reduced the price to 100?

$125 was the original price : 80% of 125 is 100.


How much is 125 kilograms?

125 kg is equal to 8 and a half slugs (which is of course 19 and a half stone, or 1,929,000 grains)