Nuclear Chemistry Question?

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Based on the following atomic mass values - ^1H, 1.00782amu; ^2H, 2.01410amu; ^3H, 3.01605; ^4H, 4.00260amu - and the mass of the neutron given in the text (1.008664916amu), calculate the energy realesed per mole in each of the following nuclear reactions, all of which are possibililtes for a controlled fusion process:
a.) 2/1 H + 3/1 H ==> 4/2 He + 1/0 n
b.) 2/1 H + 2/1 H ==> 3/2 He + 1/0 n
c.) 2/1 H + 3/2 He ==> 4/2 He + 1/1 H

I don't know where to start. Thanks
 
Compute the difference in mass between the reactants and products, then use E=mc^2 to calculate the energy released.

For instance, in (a), deuterium reacts with tritium to make helium and a neutron. Add the masses of deuterium and tritium, and then subtract the mass of helium and a neutron. The products will weigh less. This "missing mass" is converted to energy and can be calculated with Einstein's equation.

The problem is that you need the mass of He-4, which you didn't give, unless your "^3H, 3.01605; ^4H, 4.00260amu" are supposed to be for helium and not hydrogen. In which case you can do (a) as follows:

2.01410 + 3.01605 - 4.00260 - 1.008664916 = 0.018885 amu

Convert the mass in amu to kilograms, then use E=mc^2

3.13592764 x 10^-29 kg x (3 x 10^8 m/s)^2 = 2.8223 × 10^-12 J/atom

Multiply by Avogadro's number to convert to J/mol:
1.6996 x 10^12 J/mol
or
1.6996 x 10^9 kJ/mol
 
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