Answer:
Energy released by 1 g of U-235 = 7.603 * 10¹⁰ J
Step-by-step explanation:
Uranium-235, U-235 undergoes neutron-induced fission to give the following products:
1 neutron + ²³⁵U --> ¹⁴¹Ba + ⁹²Kr + 3 neutrons
Masses of reactants and products:
neutron = 1.009 amu, uranium-235 = 235.044 amu, Ba-141 = 140.910 amu, Kr-92 = 91.910 amu
mass defect = mass of reactants - mass of products
mass defect = (235.044 + 1.009) - (140.910 + 91.910 + 3 * 1.009)
mass defect = 236.053 - 235.847 = 0.206 amu
1 amu = 1.6 * 10⁻²⁷ kg
Using E = mc²
E = 0.206 * 1.6* 10⁻²⁷ kg * (3 * 10⁸ m/s)² = 2.966 * 10⁻¹¹ J
therefore, 1 atom of U-235 releases 2.966 * 10⁻¹¹ J of energy
energy released by 1 g of U-235 can be calculated as follows:
1 mole or 253 g of U-235 contains 6.02 * 10³ atoms
1 g of U-235 will contain 6.02 * 10³/235 = 2.563 * 10²¹ atoms
Energy released by 1 g of U-235 = 2.563 * 10²¹ * 2.966 * 10⁻¹¹ J = 7.603 * 10¹⁰ J