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E = mc2 - mass energy conversion

Q3. Nuclei of Po decay by the emission of an α particle to form a stable isotope of an element X. You may assume that no γ emission accompanies the decay.

(a)

(i) State the proton number of X.

(ii) State the nucleon number of X.

(2 marks)

(b) Each decaying nucleus of releases 8.6 × 10–13 J of energy.

(i) State the form in which this energy initially appears.

(ii) Using only the information provided in the question, calculate the difference in mass between the original polonium atom and the combined mass of an atom of X and an α particle.

speed of light in vacuum = 3.0 × 108 ms–1

(3 marks)

(Total 5 marks)