To determine which equation represents a fission reaction, we need to understand the types of nuclear reactions presented:
1. Fusion Reaction: This involves two light nuclei combining to form a heavier nucleus.
2. Fission Reaction: This involves a heavy nucleus splitting into two or more lighter nuclei, often accompanied by the release of neutrons.
3. Beta Decay: This involves a nucleus emitting a beta particle (electron or positron) and transforming into another element.
Let's analyze each given equation:
1. Equation 1:
[tex]\[ _7^{14} N+_1^1 H \longrightarrow _8^{15} O \][/tex]
This represents nitrogen-14 and a proton combining to form oxygen-15. This is a fusion reaction because it involves the combining of light nuclei to form a heavier nucleus.
2. Equation 2:
[tex]\[ _{92}^{235} U+_0^1 n \longrightarrow_{55}^{140} Cs +_{37}^{94} Rb+2_0^1 n \][/tex]
This represents uranium-235 absorbing a neutron and then splitting into cesium-140 and rubidium-94, along with the release of two neutrons. This is a fission reaction because a heavy nucleus is splitting into lighter nuclei.
3. Equation 3:
[tex]\[ _4^9 Be +_2^4 He \longrightarrow _6^{12} C +_0^1 n \][/tex]
This represents beryllium-9 and a helium-4 nucleus combining to form carbon-12 and a neutron. This is a fusion reaction because it involves the combining of light nuclei to form a heavier nucleus and a neutron.
4. Equation 4:
[tex]\[ _{93}^{239} Np \longrightarrow_{94}^{239} Pu +_{-1}^0 e \][/tex]
This represents neptunium-239 transforming into plutonium-239 and emitting a beta particle. This is a beta decay reaction because it involves the emission of a beta particle and transmutation of the element.
Among these reactions, the second equation:
[tex]\[_{92}^{235} U+_0^1 n \longrightarrow_{55}^{140} Cs +_{37}^{94} Rb+2_0^1 n \][/tex]
represents a fission reaction.
Therefore, the answer is the second equation.
