5) The figure shows a classical picture of the hydrogen atom, with an electron o

Question

5) The figure shows a classical picture of the hydrogen atom, with an electron orbiting a proton at distance of 2.5 X 10 -11. This was our idea of the hydrogen atom before the advent of quantum mechanics. For reference, electrons have a mass of 9.1 X 10-31 kg while protons have a mass of 1.7 X 10-27kg. Both have a charge of 1.6 X 10-19 C.

a) What forces act on the electron?

b) The electric force from Coulomb’s Law is the main force that keeps the electron attracted to the proton in the hydrogen atom. How strong is the electric force on the electron from the proton?

c) Since the orbits are circular, that means the electric force is acting as a centripetal force. Use this connection to calculate the orbital speed of the electron around the proton.

Explanation / Answer

(a)

The outward centrifugal force is balanced by the net electrostatic attraction toward the nucleus

(b)

F = k q1 q2/r^2

= 9 * 10^9 ( 1.6 * 10^-19)^2/(2.5* 10^-11)^2

=3.68* 10^-7 N

(c)

v= nh/ 2 pi mr

= 1* 6.63* 10^-34/ 2pi ( 9.1* 10^-31) ( 2.5* 10^-11)

=4.63 * 10^6 m/s

Related Questions

Navigate

• Browse (All)
• Browse 5
• Subjects

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.