Final answer:
The missing particle or type of radiation that needs to be included to balance the equation 234Th = __ + Beta Particle is a beta particle (symbol β), which is a high-speed electron emitted from the atomic nucleus during beta decay.
Step-by-step explanation:
In the equation 234Th = __ + Beta Particle, the missing particle or type of radiation that needs to be included to balance the equation is a beta particle represented by the symbol β. A beta particle is a high-speed electron that is emitted from the atomic nucleus during beta decay.
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