Question

A helium atom has a mass of mHe= 4.002604 u. When disassembled into its constituent subatomic particles (2 protons, 2 neutrons, and 2 electrons), the well separated individual particles have the following masses: mp=1.007276 u, mn=1.008665 u, and me=0.000549 u. a. How much work, in Joules, is required to completed disassemble a Helium atom? b. Estimate how much work is required to completely disassemble all the helium.

Answer 1

Answer:

28.295244 MeV

Explanation:

$m_p$ = Mass of proton = 1.007276 u

$m_n$ = Mass of neutron = 1.008665 u

$m_e$ = Mass of electron = 0.000549 u

Mass of reactant is 4.002604 u

Mass of the products is

$2\times (m_p+m_n+m_e)=2\times (1.007276+1.008665+0.000549)=4.03298\ u$

(2 because there are 2 of each)

The difference in mass is

$4.03298-4.002604=0.030376\ u$

So, the work done in MeV would be

$0.030376\times 931.5=28.295244\ MeV$

The work done required to completely disassemble all the helium is 28.295244 MeV