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Ch.20 - Radioactivity and Nuclear Chemistry
Chapter 20, Problem 78b,c

Complete each nuclear equation and calculate the energy change (in J/mol of reactant) associated with each (Al-27 = 26.981538 amu, Am-241 = 241.056822 amu, He-4 = 4.002603 amu, Np-237 = 237.048166 amu, P-30 = 29.981801 amu, S-32 = 31.972071 amu, and Si-29 = 28.976495 amu).
b. 3216S + ______ → 2914Si + 42He
c. 24195Am → 23793Np + _____

Verified step by step guidance
1
Identify the missing particle in each nuclear equation by balancing the atomic and mass numbers on both sides of the equation.
For equation b: \( ^{32}_{16}\text{S} + \text{?} \rightarrow ^{29}_{14}\text{Si} + ^{4}_{2}\text{He} \), calculate the missing particle's atomic and mass numbers by subtracting the known products from the reactant.
For equation c: \( ^{241}_{95}\text{Am} \rightarrow ^{237}_{93}\text{Np} + \text{?} \), calculate the missing particle's atomic and mass numbers by subtracting the known product from the reactant.
Calculate the mass defect for each reaction by finding the difference in mass between the reactants and products using the given atomic masses.
Use Einstein's equation \( E = \Delta m c^2 \) to calculate the energy change, where \( \Delta m \) is the mass defect in kg and \( c \) is the speed of light (\( 3.00 \times 10^8 \text{ m/s} \)). Convert the energy change to J/mol by multiplying by Avogadro's number (\( 6.022 \times 10^{23} \text{ mol}^{-1} \)).