Which of the following balanced equations represents a nuclear fusion reaction?

• A. 235 ^92U + 1 ^0n → 141 ^56Ba + 92 ^36Kr + 3 1 ^0n
• B. 2 ^1H + 3 ^1H → 4 ^2He + 1 ^0n
• C. 14 ^6C → 14 ^7N + 0 ^-1e
• D. 2 ^1H + 2 ^1H → 3 ^2He + 1 ^0n

Answer: (D)

Verified step by step guidance

1. Understand the difference between nuclear fusion and nuclear fission: Fusion is the process where two light nuclei combine to form a heavier nucleus, releasing energy. Fission is the splitting of a heavy nucleus into lighter nuclei, also releasing energy.
2. Examine each given reaction to identify whether it involves combining light nuclei (fusion) or splitting heavy nuclei (fission).
3. Look at the first reaction: \(^{235}_{92}U + ^{1}_{0}n \rightarrow ^{141}_{56}Ba + ^{92}_{36}Kr + 3 ^{1}_{0}n\). This shows a heavy uranium nucleus splitting into smaller nuclei, which is characteristic of fission.
4. Check the second reaction: \(^{2}_{1}H + ^{3}_{1}H \rightarrow ^{4}_{2}He + ^{1}_{0}n\). Here, two light nuclei (isotopes of hydrogen) combine to form a heavier helium nucleus and a neutron, which is a fusion process.
5. Confirm that the third reaction: \(^{14}_{6}C \rightarrow ^{14}_{7}N + ^{0}_{-1}e\) is a radioactive decay (beta decay), not fusion or fission.