WTA : does atomic mass matter to atom's radius?

AI Thread Summary
The discussion centers on the atomic radius ratio between Helium-3 (He-3) and Helium-4 (He-4). It is concluded that while both isotopes have the same atomic radius due to having the same number of electrons, their nuclear radii differ. The atomic radius ratio is determined to be 1, indicating they are the same. The formula R=R_0*A^(1/3) is referenced to explain the relationship between mass number and nuclear radius. Overall, the atomic radius remains unchanged between the two isotopes, while the nuclear radius varies.
adi adi
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Homework Statement


so my friend asked this question: "what's the atomic radius ratio between He-3 and He-4?"
2. Homework Equations

all i know is this equation : r =nh/mv
3. The Attempt at a Solution

i thought the ratio will be same because both He-3 and He-4 have only two electrons. Correct me if I am wrong please
 
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Nuclear radius will be different but atomic radius will remain the same. As atomic radius is the distance between the center of the nuclei to the outermost electron-which is same for both.

ratio is 1 and 'not same'
 
ash64449 said:
Nuclear radius will be different but atomic radius will remain the same. As atomic radius is the distance between the center of the nuclei to the outermost electron-which is same for both.

ratio is 1 and 'not same'
so to make clear things the ratio of atomic radius is same but the nuclear radius isn't same right?
 
adi adi said:
ratio of atomic radius is same

You should actually say atomic radius of both are same and ratio is 1.
adi adi said:
nuclear radius isn't same right?

yes. You can understand it by the formula:

R=R_0*A^(1/3)

where A-Mass number, R_0 is a constant
 
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