Final answer:
The complete α decay equation for Californium-249 is 249Cf → 245Cm + 4He, where Curium-245 is the daughter product. To calculate the energy released during the decay, one would need the specific mass values of the nuclides involved. The correct option is (a) 249Cf → 245Cm + 4He.
Step-by-step explanation:
To answer the question, we must write the complete α decay equation for 249Cf (Californium-249). Alpha (α) decay occurs when an unstable nucleus emits an alpha particle, which consists of two protons and two neutrons. This process reduces the atomic number by two and the mass number by four. Since an α particle is equivalent to a 4He (Helium-4) nucleus, removing it from 249Cf should yield a daughter nucleus with an atomic number two less than Californium (which has atomic number 98) and a mass number four less than 249. Hence, the correct option is:
Alpha Decay Equation
(a) 249Cf → 245Cm + 4He
In this equation, 245Cm represents Curium-245, which is the daughter product after the α decay. The inclusion of 4He on the right side of the equation indicates the alpha particle that is emitted during the decay. The complete and balanced nuclear equation for the α decay of Californium-249 is therefore:
249Cf → 245Cm + 4He
It’s important to note the conservation of both mass and atomic numbers in this reaction. The mass number on both sides totals 249, and the atomic number totals 98, satisfying the law of conservation of mass and charge.
To find the energy released in the decay, you would use the equation E = (Δm) c², where Δm is the mass difference between the parent nucleus and the products of the decay, and c is the speed of light. However, the specific masses of the nuclides are needed to calculate this energy, which are not provided in the question.
To summarize, the correct option is:
(a) 249Cf → 245Cm + 4He
and the energy released in the decay would be calculated if the mass values were known.