E.3 Radioactive decay

Material A decays into material B. At t = 0 the material is half A, half B. At t = 300 s the material is 25% A. What is A's half-life?

• 10 minutes

• 2 minutes

• 5 minutes

• 150 seconds

Exposure to too much radiation can cause illness. Which of the following is the least effective precaution against overexposure?

• Wearing sunglasses
• Keep radioactive isotopes to arm's lenght

• Keeping radioactive sample in a lead box

• Use tweezers to handle radioactive isotopes

The diagram shows a nuclear decay equation. What is the value of x?

• 8

• 18

• 7

• 5

The diagram shows particle traces in a cloud chamber with a perpendicular magnetic field. Particle A is an electron. What could Particle B be?

• Positron
• Proton
• Photon
• Neutron

The diagram shows a graph of binding energy per nucleon against nucleon number. Which of the following statements is false?

• A can decay into B by beta decay

• The binding energy of B is more than the binding energy in A

• B has more nucleons than A

• B is more stable than A.

Which property of a nuclide does not change as a result of beta decay?

• Atomic number
• Neutron count
• Electron configuration
• Nucleon number

Which of the following lists the particles emitted during radioactive decay in order of increasing ionizing power?

• gamma, beta, alpha

• beta, gamma, alpha

• alpha, beta, gamma

• alpha, gamma, beta

Bismuth-210 is a radioactive isotope that decay as follows:

What are the mass number A and proton number Z of Y ?

• A = 206
  Z = 86

• A = 206
  Z = 82

• A = 210
  Z = 82

• A = 214
  Z = 83

Which of the following is the correct definition of the binding energy of a nucleus

• The energy released when a nucleus forms from protons and neutrons.
• The energy required to disassemble a nucleus into its individual protons and neutrons.
• The total mass of a nucleus multiplied by the speed of light squared.
• The energy that keeps the nucleus together