Page 302 - Theory and Problems of BEGINNING CHEMISTRY

CHAP. 19] NUCLEAR REACTIONS 291

3
19.27. If 1.00 mol of C is burned to CO 2 in an ordinary chemical reaction, 393 × 10 J of energy is liberated. (a) If 12.0 g
of C could be totally converted to energy, how much energy could be liberated? (b) If 0.00100% of the mass could
be converted to energy, how much energy could be liberated?
15
8
2
15
2
2
2
Ans. (a) E = mc = (12.0 × 10 −3 kg)(3.00 × 10 m/s) = 1.08 × 10 kg·m /s = 1.08 × 10 J
15
10
(b)0.0000100(1.08 × 10 J) = 1.08 × 10 J
Over 25 000 times more energy would be liberated by converting 0.00100% of the carbon to energy
than by burning all of it chemically.