Question

What are two elements that produce background radiation on earth and what do their decay equations look like?

Answer 1

1. U₂₃₈→α→Th₂₃₄(UX₁) 
2. Th₂₂₈→α→Ra₂₂₆(MsTh₁) 

α = Alpha decay (release of He Nucleus) 
The decay products are meso states that undergo further (β) decay