Chapter 7 - Electronic Structure - Questions and Exercises - Exercises - Page 286: 7.47

2650 m/s

λ = $\frac{h}{mv}$ Or velocity, v = $\frac{h}{mλ}$ h = $6.626\times10^{-34}Js$ m = $1.67\times10^{-27} kg$ λ = 0.150 nm = $0.150\times10^{-9}m$ v = $\frac{6.626\times10^{-34}Js}{1.67\times10^{-27} kg\times0.150\times10^{-9}m}$ = 2650 m