Page 486 - Chemistry eBook

Balancing Nuclear Equations
Sometimes, the Regents will give you a nuclear equation and you will have to fill in the mass and charge and figure out what the element is. It’s very simple. Just fill in the missing pieces. The top numbers and the bottom numbers on each side must match.
212Po X + 208Pb 84 82
Find the element, mass, and charge of ‘X’.
• The mass on the left side is 212. So the mass on the right side must also equal 212.
212 – 208 = 4. The mass of X is 4, or 4X.
• The charge on the left side is 84. The charge on the right side must also equal 84.
84 – 82 = 2. The charge of X is 2 = 2X.
• Let’s put the mass and charge together: 42X
• Now, which particle has a mass of 4 and a charge of 2? Check Reffy, Table O (p. 7) and you
will see that the symbol of alpha particles is 42He. X = 42He.
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