Kinetic Energy of a hydrogen electron

AI Thread Summary
The discussion focuses on calculating the kinetic energy of a hydrogen electron using the Bohr model, with the given orbital speed of 2190 km/s. The kinetic energy formula KE = 1/2mv^2 is applied, but the user encounters an error in their calculations. They correctly convert the speed to meters per second and attempt to calculate the mass of a hydrogen atom but seem to confuse it with the mass of an electron. The user seeks clarification on the correct mass of an electron to accurately compute the kinetic energy.
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Homework Statement



In the Bohr model of the atom, the ground-state electron in hydrogen has an orbital speed of 2190 km/s. What is its kinetic energy?

Homework Equations



KE = 1/2mv^2

The Attempt at a Solution



I'm not sure what I am doing wrong but the program we use to enter homework is saying I'm wrong. So anyway kinetic energy = 1/2*m*v^2. Mass of 1 hydrogen atom = 1.008g/mol*(1mol/6.022*10^23 )*(1kg/1000g) = 1.674*10^-27 g/atom.
The speed is 2190km/s*1000m/km = 2190000m/s therefore
KE = 1/2(1.674*10^-27)(2190000)^2 = 4*10^-15 Joules
 
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It asks for the kinetic energy of the electron. What is the mass of an electron?
 

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