Free energy from Thorium to Radon

[Xeno24]

228 224 4
Th --> Ra + He
90 88 2228,031015u --> 224,020186u + 4,0026033u

228,031015u - [224,020186u + 4,0026033u]=

0,0082257u

0,0082257u x 931.49 MeV = 7662157,293eV

7662157,293eV x (1.602 x 10^-19J) =

1,2274776 x 10^-12J

Svar: Frigjorda energin är: ~ 1.23 x 10^-12JHi, people could anyone check what I've done wrong here? My teacher says the answer value is a bit too high. It's just arithmetic and I've still done something wrong...I tried multiplying the (0,0082257u) with (1.66 x 10^-27) x C^2 and I still get ~ 1.23 x 10^-12J

Thanks.

 

[Andrew Mason]

228 224 4
Th --> Ra + He
90 88 2228,031015u --> 224,020186u + 4,0026033u

228,031015u - [224,020186u + 4,0026033u]=

0,0082257u

0,0082257u x 931.49 MeV = 7662157,293eV

7662157,293eV x (1.602 x 10^-19J) =

1,2274776 x 10^-12J

Svar: Frigjorda energin är: ~ 1.23 x 10^-12JHi, people could anyone check what I've done wrong here? My teacher says the answer value is a bit too high. It's just arithmetic and I've still done something wrong...I tried multiplying the (0,0082257u) with (1.66 x 10^-27) x C^2 and I still get ~ 1.23 x 10^-12J

Thanks.

Your answer appears to be right.

From E = mc^2:

Just multiply the mass difference in kg. by c^2 in m/sec. to get the energy in joules

Mass difference is 8.226x10^-3 amu. One kg = 1000 x 6.02x10^23 amu so one amu = 1.66 x 10^-27 kg. Multiply that by (3 x 10^8 m/sec)^2 to get the energy in J. per amu. (= 1.49 x 10^-10 J.). So that works out to 8.266x10^-3 x 1.49 x 10^-10 = 12.3 x 10^-13 J = 1.23x10^-12 J.

AM