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Your Questions About How To Discover New Elements

Mary asks…

What will be the average atomic mass of this element?

Suppose that a newly discovered element called centium has three isotopes that occur in nature. These are centium-200, centium-203, and centium-209. Assume that these isotopes occur in equal amounts in nature.

New Niche Finder answers:

204

John asks…

What is the weighted average atomic mass for this element?

A newly discovered element, X, has two naturally occurring isotopes. 87.8 percent of the sample is an isotope with a mass of 267.8 u, and 12.2 percent of the sample is an isotope with a mass of 269.9 u. What is the weighted average atomic mass for this element?

267.9 u

268.1 u

268.9 u

269.1 u

New Niche Finder answers:

(0.878) (267.8 u) + (0.122) (269.9 u) = 268.1 u

David asks…

What is the weighted average atomic mass for this element?

A newly discovered element, Y, has two naturally occurring isotopes. 87.8 percent of the sample is an isotope with a mass of 267.8 u, and 12.2 percent of the sample is an isotope with a mass of 269.9 u. What is the weighted average atomic mass for this element?

A.267.9 u

B.268.1 u

C.268.9 u

D. 269.1 u

New Niche Finder answers:

(0.878)(267.8) + (.122)(269.9) = 268.1 g/mol (B)

Robert asks…

how to find the average atomic mass of an element?

This is what the question says: Suppose that a newly discovered element called centium has three isotopes that ocfur in nature. These are centium-200, centium-203, and centium-209. Assume that these isotopes occur in equal amounts in nature. What will be the average atomic mass of this element?

I need help w/this because i was absent not because im lazy so if your just going to say that im lying about that don’t even answer please. If you do answer, thanks for your help.

New Niche Finder answers:

(200) (0.33) + (203) (0.33) + (209) (0.33) = the answer you seek

Some more examples here:

http://www.chemteam.info/Mole/AverageAtomicWeight.html

Thomas asks…

How do scientists determine what elements make up a star?

I was watching “The Universe” on the History Channel the other day. I know for time sake most programs gloss over certain things to address the main ideas. Can anyway tell me in a simple way how scientists discover what elements make up a star? I know that hydrogen converts to helium and etc. I am just wondering how scientists know that it is hydrogen, for example. Thank you very much!

New Niche Finder answers:

By the spectra of their light.
Specially the dark absorption lines which are typical of every element.

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