Nuclear and Particle Physics Nuclear and Particle Physics Help Forum May 13th 2019, 01:16 PM #1 Junior Member   Join Date: May 2019 Posts: 3 Calculate the mass deficit in this nuclear reaction Calculate the mass deficit in this nuclear reaction $12{\rm C}+\frac{12}{6}{\rm C}\rightarrow \frac{24}{12}{\rm Mg}$ Information given: - rest mass of a carbon-12 nucleus: $1.9921157\times 10^{-26}\,{\rm kg}$ - rest mass of a magnesium nucleus: $3.9817469\times 10^{-26}\,{\rm kg}$ - rest mass of a proton: $1.67353\times 10^{-27}\,{\rm kg}$ - rest mass of a neutron: $1.67492\times 10^{-27}\,{\rm kg}$ - speed of light: $3.00\times 10^{8}\,{\rm m}\,{\rm s}^{-1}$ My attempts so far haven't been great I'm thinking along the line of using a formula but even then I don't know what variables to plug in where. thanks Last edited by subarua; May 13th 2019 at 01:23 PM.   May 29th 2019, 08:13 AM #2 Senior Member   Join Date: Oct 2017 Location: Glasgow Posts: 395 $\displaystyle \Delta m = 3.9817469\times 10^{-26} - 2 (1.9921157\times 10^{-26}) = - 0.0024845 \times 10^{-26} = -2.4845 \times 10^{-29} kg = -13.937 MeV/c^2$ Last edited by benit13; May 29th 2019 at 08:15 AM.   May 29th 2019, 04:15 PM #3 Senior Member   Join Date: Jun 2016 Location: England Posts: 933 Is this a correct interpretation? I am unfamiliar with the notation used by subarua. However I guess that 12/6 against the Carbon indicates Carbon 12 with 6 protons (thus also 6 neutrons) and similarly 24/12 indicates Magnetism 24 with 12 protons (and 12 neutrons) Or perhaps the notation indicates Carbon 12 with 6 neutrons... Either way this would then suggest that the original equation provided should have both carbons preceded by 12/6. topsquark likes this. __________________ ~\o/~   May 30th 2019, 02:20 AM   #4
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 I am unfamiliar with the notation used by subarua. However I guess that 12/6 against the Carbon indicates Carbon 12 with 6 protons (thus also 6 neutrons) and similarly 24/12 indicates Magnetism 24 with 12 protons (and 12 neutrons) Or perhaps the notation indicates Carbon 12 with 6 neutrons... Either way this would then suggest that the original equation provided should have both carbons preceded by 12/6.
Yeah it's

$\displaystyle ^{12}_{6}C + ^{12}_{6}C = ^{24}_{12}Mg$,

but it's typical to leave out the atomic number since you can identify that from the element, so reactions are typically stated using

$\displaystyle ^{12}C + ^{12}C = ^{24}Mg$

or in the nucleosynthesis literature:

$\displaystyle ^{12}C(^{12}C, \gamma) ^{24}Mg$  Tags calculate, deficit, mass, nuclear, reaction Thread Tools Show Printable Version Email this Page Display Modes Linear Mode Switch to Hybrid Mode Switch to Threaded Mode Similar Physics Forum Discussions Thread Thread Starter Forum Replies Last Post Samy89 Nuclear and Particle Physics 0 May 6th 2019 04:22 AM jackthehat Kinematics and Dynamics 2 Oct 5th 2017 08:47 PM ling233 Nuclear and Particle Physics 2 Nov 17th 2016 09:13 PM ling233 Quantum Physics 1 Oct 10th 2014 10:01 AM Devlan Nuclear and Particle Physics 2 Apr 21st 2013 11:25 AM 