Physics 0625 · IGCSE · Radioactivity

Radioactivity — practice question

This actinium isotope has a nucleus containing 89 protons and 136 neutrons. The chemical symbol for actinium is Ac.
(a(i))[1]

Write the nuclide notation for this actinium isotope.

(a(ii))[1]

State how many electrons are present around the nucleus of a neutral atom of this isotope.

(b)[3]

On Fig. 10.1, add two further points to show the mass remaining after 20 days and 30 days. Then draw the decay curve for the sample over 30 days.

Worked solution & mark scheme

This 5-mark question has a full step-by-step worked solution and mark scheme. One marking point: 225 as the nucleon number; 89 as the proton number (Ac)

  • Full mark scheme, point by point
  • Step-by-step worked solution
  • Write your answer & get it marked instantly by AI