If `13.6eV` energy is required to separate a hydrogen atom into a proton and an electron, then the orbital radius of electron in a hydrogen atom is
A. `5.3xx10^(-11)m`
B. `4.3xx10^(-11)m`
C. `6.3xx10^(-11)m`
D. `7.3xx10^(-11)m`
Correct Answer - A
Here, `E=-13.6eV=-13.6xx1.6xx10^(-19)=-2.2xx10^(-18)J`
`E=(-e^2)/(8piepsilon_0r)`
`therefore` As orbital radius,
`r=(-e^2)/(8piepsilon_0E)=(9xx10^(9)xx(1.6xx10^(-19))^2)/(2xx(2.2xx10^(-18)))=5.3xx10^(-11)m`.
Given ,total energy of the electron `E=-4.6 EV`
(i) Kinetic energy of electron K=-(Total energy E,)
`rArr " " =-E=-(-4.6)=4.6 eV`
(ii) de- Brogile wavelength
`lambda_(d)=(h)/(sqrt(2 mK))=(6.6xx10^(-34))/(sqrt(2xx9.1xx10^(-31)xx4.6xx1.6xx10^(-19)))`
`0.57xx10^(-9)m=0.57 nm`
Correct Answer - d
`k=(1)/(2)mv^(2)`.In electric field,`Y =(qEx^(2))/(2mv^(2))=(qEx^(2))/(4k)`
The curvature of the trajectory is proportional to `qE//K` since q,E and K are same for btoth particles ,hence the trajectories will have...
Correct Answer - C
Here the ground state energy , (E) `=-13.6eV` since, K.E. of the electron `=-13.6eV`
`=13-6xx1.6xx10^(-19)J=21.76xx10^(-19)J=2.18xx10^(-18)J`.