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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

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  1. 1. A radioactive parent nucleus has nucleon (mass) number A = 221 and proton (atomic) number Z = 82. It undergoes alpha (α) decay to form a daughter nucleus. Find the proton number Z of the daughter nucleus.

    Parent: A = 221, Z = 82 (alpha (α)) · Daughter Proton Number Z = ?
  2. 2. A radioactive parent nucleus has nucleon (mass) number A = 235 and proton (atomic) number Z = 94. It undergoes beta-minus (β⁻) decay to form a daughter nucleus. Find the nucleon number A of the daughter nucleus.

    Parent: A = 235, Z = 94 (beta-minus (β⁻)) · Daughter Nucleon Number A = ?
  3. 3. A radioactive parent nucleus has nucleon (mass) number A = 235 and proton (atomic) number Z = 90. It undergoes beta-minus (β⁻) decay to form a daughter nucleus. Find the nucleon number A of the daughter nucleus.

    Parent: A = 235, Z = 90 (beta-minus (β⁻)) · Daughter Nucleon Number A = ?
  4. 4. A radioactive parent nucleus has nucleon (mass) number A = 239 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 = 239, Z = 93 (beta-minus (β⁻)) · Daughter Nucleon Number A = ?
  5. 5. A radioactive parent nucleus has nucleon (mass) number A = 236 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 = 236, Z = 94 (beta-minus (β⁻)) · Daughter Proton Number Z = ?
  6. 6. A radioactive parent nucleus has nucleon (mass) number A = 228 and proton (atomic) number Z = 84. It undergoes beta-minus (β⁻) decay to form a daughter nucleus. Find the nucleon number A of the daughter nucleus.

    Parent: A = 228, Z = 84 (beta-minus (β⁻)) · Daughter Nucleon Number A = ?
  7. 7. A radioactive parent nucleus has nucleon (mass) number A = 226 and proton (atomic) number Z = 84. It undergoes alpha (α) decay to form a daughter nucleus. Find the proton number Z of the daughter nucleus.

    Parent: A = 226, Z = 84 (alpha (α)) · Daughter Proton Number Z = ?
  8. 8. A radioactive parent nucleus has nucleon (mass) number A = 240 and proton (atomic) number Z = 89. It undergoes beta-minus (β⁻) decay to form a daughter nucleus. Find the nucleon number A of the daughter nucleus.

    Parent: A = 240, Z = 89 (beta-minus (β⁻)) · Daughter Nucleon Number A = ?
  9. 9. A radioactive parent nucleus has nucleon (mass) number A = 228 and proton (atomic) number Z = 85. It undergoes alpha (α) decay to form a daughter nucleus. Find the nucleon number A of the daughter nucleus.

    Parent: A = 228, Z = 85 (alpha (α)) · Daughter Nucleon Number A = ?
  10. 10. 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 = ?
  11. 11. A radioactive parent nucleus has nucleon (mass) number A = 220 and proton (atomic) number Z = 82. It undergoes alpha (α) decay to form a daughter nucleus. Find the nucleon number A of the daughter nucleus.

    Parent: A = 220, Z = 82 (alpha (α)) · Daughter Nucleon Number A = ?
  12. 12. A radioactive parent nucleus has nucleon (mass) number A = 235 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 = 235, Z = 91 (beta-minus (β⁻)) · Daughter Nucleon Number A = ?
12 questions · Seed 47 · Age guidance, not curriculum certification
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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 = 221 and proton (atomic) number Z = 82. It undergoes alpha (α) decay to form a daughter nucleus. Find the proton number Z of the daughter nucleus.

    80

    In alpha (⁴₂He) decay, A decreases by 4 (221 − 4 = 217) and Z decreases by 2 (82 − 2 = 80).

  2. 2. A radioactive parent nucleus has nucleon (mass) number A = 235 and proton (atomic) number Z = 94. It undergoes beta-minus (β⁻) decay to form a daughter nucleus. Find the nucleon number A of the daughter nucleus.

    235

    In beta-minus (⁰₋₁e) decay, a neutron becomes a proton so A remains 235 and Z increases by 1 (94 + 1 = 95).

  3. 3. A radioactive parent nucleus has nucleon (mass) number A = 235 and proton (atomic) number Z = 90. It undergoes beta-minus (β⁻) decay to form a daughter nucleus. Find the nucleon number A of the daughter nucleus.

    235

    In beta-minus (⁰₋₁e) decay, a neutron becomes a proton so A remains 235 and Z increases by 1 (90 + 1 = 91).

  4. 4. A radioactive parent nucleus has nucleon (mass) number A = 239 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.

    239

    In beta-minus (⁰₋₁e) decay, a neutron becomes a proton so A remains 239 and Z increases by 1 (93 + 1 = 94).

  5. 5. A radioactive parent nucleus has nucleon (mass) number A = 236 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 236 and Z increases by 1 (94 + 1 = 95).

  6. 6. A radioactive parent nucleus has nucleon (mass) number A = 228 and proton (atomic) number Z = 84. It undergoes beta-minus (β⁻) decay to form a daughter nucleus. Find the nucleon number A of the daughter nucleus.

    228

    In beta-minus (⁰₋₁e) decay, a neutron becomes a proton so A remains 228 and Z increases by 1 (84 + 1 = 85).

  7. 7. A radioactive parent nucleus has nucleon (mass) number A = 226 and proton (atomic) number Z = 84. It undergoes alpha (α) decay to form a daughter nucleus. Find the proton number Z of the daughter nucleus.

    82

    In alpha (⁴₂He) decay, A decreases by 4 (226 − 4 = 222) and Z decreases by 2 (84 − 2 = 82).

  8. 8. A radioactive parent nucleus has nucleon (mass) number A = 240 and proton (atomic) number Z = 89. It undergoes beta-minus (β⁻) decay to form a daughter nucleus. Find the nucleon number A of the daughter nucleus.

    240

    In beta-minus (⁰₋₁e) decay, a neutron becomes a proton so A remains 240 and Z increases by 1 (89 + 1 = 90).

  9. 9. A radioactive parent nucleus has nucleon (mass) number A = 228 and proton (atomic) number Z = 85. It undergoes alpha (α) decay to form a daughter nucleus. Find the nucleon number A of the daughter nucleus.

    224

    In alpha (⁴₂He) decay, A decreases by 4 (228 − 4 = 224) and Z decreases by 2 (85 − 2 = 83).

  10. 10. 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).

  11. 11. A radioactive parent nucleus has nucleon (mass) number A = 220 and proton (atomic) number Z = 82. It undergoes alpha (α) decay to form a daughter nucleus. Find the nucleon number A of the daughter nucleus.

    216

    In alpha (⁴₂He) decay, A decreases by 4 (220 − 4 = 216) and Z decreases by 2 (82 − 2 = 80).

  12. 12. A radioactive parent nucleus has nucleon (mass) number A = 235 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.

    235

    In beta-minus (⁰₋₁e) decay, a neutron becomes a proton so A remains 235 and Z increases by 1 (91 + 1 = 92).

12 questions · Seed 47 · Age guidance, not curriculum certification