Quelpr
4 marksRadioactive Emissions

CSEC Physics · 1988 · Paper 2 · Question 3(b)(i)

A thorium decay series is given: ²³²₉₀Th -> ²²⁸₈₈Ra -> ²²⁸₈₉Ac -> ²²⁸₉₀Th.

Enter, above each arrow, the symbols for the radiations that are likely to be emitted.

The mark scheme is shown once you've answered.

Practise this question

Other parts of this question

  1. 3(a)(i)Identify the components X, Y and Z labelled in the diagram.[3 marks]
  2. 3(a)(ii)State whether or not the atom is neutral and explain your answer. Then record the mass (nucleon) number of the atom.[3 marks]
  3. 3(a)(iii)Draw a similar diagram to represent an isotope of the atom in (ii), and record its mass (nucleon) number.[3 marks]
  4. 3(b)(ii)If someone is exposed to all three radiations from the thorium source, which one do you think is most likely to cause the greatest harm? Explain your answer.[3 marks]
  5. 3(b)(iii)Calculate the half-life of a radioactive substance whose activity falls to 25% in 10 hours.[2 marks]
  6. 3(b)(iv)The activity of a substance falls from 3 000 Bq to 750 Bq in 10 hours. What is its activity after a further fifteen hours?[2 marks]

More practice: the rest of this paper · more Radioactive Emissions questions · all CSEC Physics past papers