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ScienceAges 16-18

Alpha (α) & beta (β) nuclear decay

Balance nucleon (mass) number A and proton (atomic) number Z across alpha (α) and beta-minus (β⁻) radioactive decay equations. Review suitability for your learners before teaching.

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Worksheet StudioPractice pack · Ages 16-18

Alpha (α) & beta (β) nuclear decay

Take your time. Show your thinking.

  1. 1. A radioactive parent nucleus has nucleon (mass) number A = 232 and proton (atomic) number Z = 93. It undergoes alpha (α) decay to form a daughter nucleus. Find the nucleon number A of the daughter nucleus.

    Parent: A = 232, Z = 93 (alpha (α)) · Daughter Nucleon Number A = ?
  2. 2. A radioactive parent nucleus has nucleon (mass) number A = 238 and proton (atomic) number Z = 89. It undergoes beta-minus (β⁻) decay to form a daughter nucleus. Find the proton number Z of the daughter nucleus.

    Parent: A = 238, Z = 89 (beta-minus (β⁻)) · Daughter Proton Number Z = ?
  3. 3. A radioactive parent nucleus has nucleon (mass) number A = 221 and proton (atomic) number Z = 86. It undergoes alpha (α) decay to form a daughter nucleus. Find the nucleon number A of the daughter nucleus.

    Parent: A = 221, Z = 86 (alpha (α)) · Daughter Nucleon Number A = ?
  4. 4. A radioactive parent nucleus has nucleon (mass) number A = 236 and proton (atomic) number Z = 87. It undergoes alpha (α) decay to form a daughter nucleus. Find the proton number Z of the daughter nucleus.

    Parent: A = 236, Z = 87 (alpha (α)) · Daughter Proton Number Z = ?
  5. 5. A radioactive parent nucleus has nucleon (mass) number A = 224 and proton (atomic) number Z = 88. It undergoes alpha (α) decay to form a daughter nucleus. Find the proton number Z of the daughter nucleus.

    Parent: A = 224, Z = 88 (alpha (α)) · Daughter Proton Number Z = ?
  6. 6. A radioactive parent nucleus has nucleon (mass) number A = 235 and proton (atomic) number Z = 95. It undergoes beta-minus (β⁻) decay to form a daughter nucleus. Find the proton number Z of the daughter nucleus.

    Parent: A = 235, Z = 95 (beta-minus (β⁻)) · Daughter Proton Number Z = ?
  7. 7. A radioactive parent nucleus has nucleon (mass) number A = 232 and proton (atomic) number Z = 93. It undergoes beta-minus (β⁻) decay to form a daughter nucleus. Find the nucleon number A of the daughter nucleus.

    Parent: A = 232, Z = 93 (beta-minus (β⁻)) · Daughter Nucleon Number A = ?
  8. 8. A radioactive parent nucleus has nucleon (mass) number A = 239 and proton (atomic) number Z = 94. It undergoes beta-minus (β⁻) decay to form a daughter nucleus. Find the proton number Z of the daughter nucleus.

    Parent: A = 239, Z = 94 (beta-minus (β⁻)) · Daughter Proton Number Z = ?
  9. 9. A radioactive parent nucleus has nucleon (mass) number A = 222 and proton (atomic) number Z = 88. It undergoes alpha (α) decay to form a daughter nucleus. Find the proton number Z of the daughter nucleus.

    Parent: A = 222, Z = 88 (alpha (α)) · Daughter Proton Number Z = ?
  10. 10. A radioactive parent nucleus has nucleon (mass) number A = 227 and proton (atomic) number Z = 83. It undergoes beta-minus (β⁻) decay to form a daughter nucleus. Find the proton number Z of the daughter nucleus.

    Parent: A = 227, Z = 83 (beta-minus (β⁻)) · Daughter Proton Number Z = ?
  11. 11. A radioactive parent nucleus has nucleon (mass) number A = 221 and proton (atomic) number Z = 87. It undergoes alpha (α) decay to form a daughter nucleus. Find the nucleon number A of the daughter nucleus.

    Parent: A = 221, Z = 87 (alpha (α)) · Daughter Nucleon Number A = ?
  12. 12. A radioactive parent nucleus has nucleon (mass) number A = 232 and proton (atomic) number Z = 91. It undergoes beta-minus (β⁻) decay to form a daughter nucleus. Find the nucleon number A of the daughter nucleus.

    Parent: A = 232, Z = 91 (beta-minus (β⁻)) · Daughter Nucleon Number A = ?
12 questions · Seed 104731 · Age guidance, not curriculum certification
View the answer key
Worksheet StudioAnswer key · Ages 16-18

Alpha (α) & beta (β) nuclear decay

Answers and reasoning. Review before teaching.

  1. 1. A radioactive parent nucleus has nucleon (mass) number A = 232 and proton (atomic) number Z = 93. It undergoes alpha (α) decay to form a daughter nucleus. Find the nucleon number A of the daughter nucleus.

    228

    In alpha (⁴₂He) decay, A decreases by 4 (232 − 4 = 228) and Z decreases by 2 (93 − 2 = 91).

  2. 2. A radioactive parent nucleus has nucleon (mass) number A = 238 and proton (atomic) number Z = 89. It undergoes beta-minus (β⁻) decay to form a daughter nucleus. Find the proton number Z of the daughter nucleus.

    90

    In beta-minus (⁰₋₁e) decay, a neutron becomes a proton so A remains 238 and Z increases by 1 (89 + 1 = 90).

  3. 3. A radioactive parent nucleus has nucleon (mass) number A = 221 and proton (atomic) number Z = 86. It undergoes alpha (α) decay to form a daughter nucleus. Find the nucleon number A of the daughter nucleus.

    217

    In alpha (⁴₂He) decay, A decreases by 4 (221 − 4 = 217) and Z decreases by 2 (86 − 2 = 84).

  4. 4. A radioactive parent nucleus has nucleon (mass) number A = 236 and proton (atomic) number Z = 87. It undergoes alpha (α) decay to form a daughter nucleus. Find the proton number Z of the daughter nucleus.

    85

    In alpha (⁴₂He) decay, A decreases by 4 (236 − 4 = 232) and Z decreases by 2 (87 − 2 = 85).

  5. 5. A radioactive parent nucleus has nucleon (mass) number A = 224 and proton (atomic) number Z = 88. It undergoes alpha (α) decay to form a daughter nucleus. Find the proton number Z of the daughter nucleus.

    86

    In alpha (⁴₂He) decay, A decreases by 4 (224 − 4 = 220) and Z decreases by 2 (88 − 2 = 86).

  6. 6. A radioactive parent nucleus has nucleon (mass) number A = 235 and proton (atomic) number Z = 95. It undergoes beta-minus (β⁻) decay to form a daughter nucleus. Find the proton number Z of the daughter nucleus.

    96

    In beta-minus (⁰₋₁e) decay, a neutron becomes a proton so A remains 235 and Z increases by 1 (95 + 1 = 96).

  7. 7. A radioactive parent nucleus has nucleon (mass) number A = 232 and proton (atomic) number Z = 93. It undergoes beta-minus (β⁻) decay to form a daughter nucleus. Find the nucleon number A of the daughter nucleus.

    232

    In beta-minus (⁰₋₁e) decay, a neutron becomes a proton so A remains 232 and Z increases by 1 (93 + 1 = 94).

  8. 8. A radioactive parent nucleus has nucleon (mass) number A = 239 and proton (atomic) number Z = 94. It undergoes beta-minus (β⁻) decay to form a daughter nucleus. Find the proton number Z of the daughter nucleus.

    95

    In beta-minus (⁰₋₁e) decay, a neutron becomes a proton so A remains 239 and Z increases by 1 (94 + 1 = 95).

  9. 9. A radioactive parent nucleus has nucleon (mass) number A = 222 and proton (atomic) number Z = 88. It undergoes alpha (α) decay to form a daughter nucleus. Find the proton number Z of the daughter nucleus.

    86

    In alpha (⁴₂He) decay, A decreases by 4 (222 − 4 = 218) and Z decreases by 2 (88 − 2 = 86).

  10. 10. A radioactive parent nucleus has nucleon (mass) number A = 227 and proton (atomic) number Z = 83. It undergoes beta-minus (β⁻) decay to form a daughter nucleus. Find the proton number Z of the daughter nucleus.

    84

    In beta-minus (⁰₋₁e) decay, a neutron becomes a proton so A remains 227 and Z increases by 1 (83 + 1 = 84).

  11. 11. A radioactive parent nucleus has nucleon (mass) number A = 221 and proton (atomic) number Z = 87. It undergoes alpha (α) decay to form a daughter nucleus. Find the nucleon number A of the daughter nucleus.

    217

    In alpha (⁴₂He) decay, A decreases by 4 (221 − 4 = 217) and Z decreases by 2 (87 − 2 = 85).

  12. 12. A radioactive parent nucleus has nucleon (mass) number A = 232 and proton (atomic) number Z = 91. It undergoes beta-minus (β⁻) decay to form a daughter nucleus. Find the nucleon number A of the daughter nucleus.

    232

    In beta-minus (⁰₋₁e) decay, a neutron becomes a proton so A remains 232 and Z increases by 1 (91 + 1 = 92).

12 questions · Seed 104731 · Age guidance, not curriculum certification