1% speed of light de Broglie wavelength 1.46×10^(-3) pm

1% speed of light de Broglie wavelength 1.46×10^(-3) pm

 

 

An atom of a particular element is traveling at 1% of the speed of light.

Consider an atom traveling at 1% of the speed of light.

The de Broglie wavelength is found to be 1.46×10^(-3) pm.

Which element is this?

A) Be

B) Zr

C) Kr

D) Fe

E) P

 

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드브로이의 물질파

λ = h / mc

( 참고 https://ywpop.tistory.com/3539 )

 

m = h / λc

= (6.626×10^(-34) kg•m^2/s) / [(1.46×10^(-3) pm) (10^(-12) m / 1 pm) (2.998×10^8 m/s) (1/100)]

= (6.626×10^(-34)) / [(1.46×10^(-3)) (10^(-12)) (2.998×10^8) (1/100)]

= 1.51×10^(-25) kg

---> 1개 원자의 질량

 

 

 

(1.51×10^(-25) kg/atom) (6.022×10^23 atoms/mol) (1000 g / 1 kg)

= (1.51×10^(-25)) (6.022×10^23) (1000)

= 90.9 g/mol

 

 

 

답: B) Zr