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Question

I have two worksheets with two questions about half-life but I don't get it the first question is

1.The element bismuth-214 has a half-life of only about 20 minutes

How much of 1kg of bismuth is left after 1 hour?

and the second

2.The element radium-226 decays with a half-life of 1600 years.

How

Many years have passed since 250g of 1kg of radium-226 remained?

Thank you in advance

ultrarunner · Answer

One hour here are 3 half-life times, after which 1/8 of the original quantity is still present, in this case 1/8 kg. This is 1/4 of the original amount. For this it takes 2 half-life, here is 3200 years.

frage1997407 · Answer

Just ask ChatGPT ;)

franz1957 · Answer

Remarks:

There is something wrong in the task.

The element Bismuth-214
The element Radium-226

Bismuth-214 and Radium-226 are no elements, there are nuclides.

Bismuth and radium are elements. The nuclide bismuth-214 is an isotope of the element bismuth. The nuclide radium-226 is an isotope of the element radium.

There are many other bismuth isotopes and radium isotopes. They differ from the number of neutrons in the nucleus.

One element includes all nuclides whose cores contain a certain number of protons. The proton number determines which element it is.

All isotopes of the element bismuth have 83 protons in the core. All nuclides that have 83 protons in the core are bismuth isotopes. Bismuth-209 is the most common bismuth isotope.

All isotopes of the element radium have 88 protons in the core. All nuclides that have 88 protons in the core are radium isotopes.

https://www.leifiphysik.de/kern-particle physics/kernel physics-based/basic knowledge/building-of-atomic nuclei