Q-value of nuclear reactions Questions

1. Calculate the Q-value of the reaction: $ _4^9Be\left(\ _2^4He,n\right)\ _6^{12}C$. Given Mass $\left(\ ^9Be\right)=9.012183u$ Mass $\left(\ ^4He\right)=4.002603u$ Mass $\left(\ ^{12}C\right)=12.000u$ [Mains 2005]

2. Distinguish between a nuclear reaction and decay. Which conservation laws are obeyed in nuclear reactions? Explain the significance of Q value. Calculate the Q value for the following nuclear reaction $ _1^2H+\ _1^2H=\ _2^3He+n$ [Mains 2003]