Question

Particle Mass (g/mol) 01e 0.00054858 11H 1.00782 42He 4.00260 Part A The sun produces energy via fusion. One of the fusion reactions that occurs in the sun is 411H→42He+201e How much energy in joules is released by the fusion of 2.88 g of hydrogen-1? Express your answer to three significant figures and include the appropriate units.

Answer 1

For the given fusion reaction

mass defect (m) = mass of products - mass of reactants

                          = (4 x 1.00728) - (4.00260 + 2 x 0.00054858)

                          = 0.025423 amu

c = 3 c 10^8 m/s

Energy = mc^2 = (0.025423 amu x 1.6603 x 10^-27)(3 x 10^8)^2 = 3.80 x 10^-12 J

moles of H-1 = 2.88 g/1.00728 g = 2.86 mol

Energy released by 2.88 g of H-1 = 2.86 mol x 3.80 x 10^-12 J = 1.087 x 10^-11 J