In: Chemistry
An electron, with a mass of 9.11×10−28 g is orbiting the nucleus of a hydrogen atom. A measurement determines the position of the electron to within ±1.63 nm. The velocity of the electron is measured as 6.39×106 m/s. What is the uncertainty in the velocity of the electron?
Given mass of electron, m = 9.11 * 10-28 g = 9.11 * 10-28 g * (1 kg / 1000g) = 9.11 * 10-31 Kg
uncertainity in the position of electron, x = +/- 1.63 nm = +/- 1.63 * 10-9 m
According to Heisenberg uncertainity principle,
x * P h / 4
=> x * (m * u) h / 4
=> (1.63 * 10-9 m) * 9.11 * 10-31 Kg * u ) (6.626 * 10-34 m2Kg.s-1) / (4 * 3.14)
=> 1.485*10-39 * u 5.2755*10-35
=> u 3.55 * 104 m/s
Hence uncertainity in the velocity of electron is 3.55 * 104 m/s (answer)