NEET2018ChemistryStructure of AtomActual
The position of both an electron and helium atom is known within 1.0 ~nm . The momentum of the electron is known within 5.0 10⁻²⁶ ~kg ~m ~s ⁻¹ . The minimum uncertainty in the measurement of the momentum of the helium atom is
Options
- A7.0 10⁻²⁶ ~kg ~m ~s ⁻¹
- B5.0 10⁻²⁶ ~kg ~m ~s ⁻¹
- C8.0 10⁻²⁶ ~kg ~m ~s ⁻¹
- D6.0 10⁻²⁶ ~kg ~m ~s ⁻¹
Correct answer
B. 5.0 10⁻²⁶ ~kg ~m ~s ⁻¹
Step-by-step solution
The Heisenberg uncertainty principle, x p h 4 , where x= Uncertainty in position, p= Uncertainty in momentum and h / 4 = constant. As x is same for electron and helium and h / 4 is a constant, therefore minimum uncertainty in the measurement of the momentum of the helium atom will be same as that of an electron which is 5.0 10⁻²⁶ ~kg ~m ~s ⁻¹ .