Verify that the total number of nucleons, and total charge are conserved for each of the following fusion reactions in the proton-proton chain. (i) \(^{1} \mathrm{H}+^{1} \mathrm{H} \rightarrow^{2} \mathrm{H}+e^{+}+v_{\mathrm{e}},\) (ii) \(^{1} \mathrm{H}+^{2} \mathrm{H} \rightarrow^{3} \mathrm{He}+\gamma,\) and (iii) \(^{3} \mathrm{He}+^{3} \mathrm{He} \rightarrow^{4} \mathrm{He}+^{1} \mathrm{H}+^{1} \mathrm{H}\). (List the value of each of the conserved quantities before and after each of the reactions.)

Short Answer

Expert verified
In all three fusion reactions in the proton-proton chain, the total number of nucleons and total charge are conserved: (i) \(^{1}H + ^{1}H \rightarrow ^{2}H + e^{+} +v_{e}\): nucleons (2) and charge (+2) conserved. (ii) \(^{1}H + ^{2}H \rightarrow ^{3}He + \gamma\): nucleons (3) and charge (+2) conserved. (iii) \(^{3}He + ^{3}He \rightarrow ^{4}He + ^{1}H + ^{1}H\): nucleons (6) and charge (+4) conserved.

Step by step solution

01

(i) First Reaction

\(^{1}H + ^{1}H \rightarrow ^{2}H + e^{+} +v_{e}\) Before the reaction: Total number of nucleons = Number of protons + Number of neutrons = 1 + 1 = 2 Total charge = Charge of Protons = +1 +1 = +2 After the reaction: Total number of nucleons = Number of protons + Number of neutrons = 1 + 1 = 2 Total charge = Charge of Deuteron + Charge of positron = +1 + 1 = +2 From the before and after calculations, we can see that the total number of nucleons (2) and total charge (+2) are conserved.
02

(ii) Second Reaction

\(^{1}H + ^{2}H \rightarrow ^{3}He + \gamma\) Before the reaction: Total number of nucleons = Number of protons + Number of neutrons = 1 + 2 = 3 Total charge = Charge of Protons = +1 +1 = +2 After the reaction: Total number of nucleons = Number of protons + Number of neutrons = 2 + 1 = 3 Total charge = Charge of Helium-3 = +2 From the before and after calculations, we can see that the total number of nucleons (3) and total charge (+2) are conserved.
03

(iii) Third Reaction

\(^{3}He + ^{3}He \rightarrow ^{4}He + ^{1}H + ^{1}H\) Before the reaction: Total number of nucleons = Number of protons + Number of neutrons = 3 + 3 = 6 Total charge = Charge of Protons = +2 + 2 = +4 After the reaction: Total number of nucleons = Number of protons + Number of neutrons = 2 + 2 + 1 + 1 = 6 Total charge = Charge of Helium-4 + Charge of Protons = +2 +1 +1 = +4 From the before and after calculations, we can see that the total number of nucleons (6) and total charge (+4) are conserved.

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