Unstable Nuclei and Radioactive Decay

The graph of neutron number against proton number shows three nuclei P, Q and R.

Which of the following identifies an isotope of P and the nucleon number of this isotope of P?

• Isotope of P: Q

  Nucleon number of isotope of P: y + 1

• Isotope of P: Q

  Nucleon number of isotope of P: x + y + 1

• Isotope of P: R

  Nucleon number of isotope of P: x + y + 1

• Isotope of P: R

  Nucleon number of isotope of P: x + 1

Tags

NGSS.HS-PS1-7

²³⁶₉₂U undergoes a series of decays to produce ²⁰⁴₈₂Pb

How many alpha decays are involved in this decay series?

• 5

• 6

• 8

• 10

Tags

NGSS.HS-PS1-8

An iodine nucleus decays into a nucleus of Xe−131, a beta-minus particle and particle Y.

Which is a property of particle Y?

• It has a lepton number of +1

• It is an antiparticle

• It is negatively charged

• It experiences the strong interaction

Tags

NGSS.HS-PS1-8

When a nucleus of the radioactive isotope ⁶⁵₂₈Ni decays, a β^– particle and an electron antineutrino are emitted.

How many protons and neutrons are there in the resulting daughter nucleus?

• Number of protons: 28

  Number of neutrons: 65

• Number of protons: 29

  Number of neutrons: 65

• Number of protons: 29

  Number of neutrons: 36

• Number of protons: 30

  Number of neutrons: 35

Tags

NGSS.HS-PS1-8

²³²₉₀Th is an unstable nuclide in a radioactive decay series. It decays by emitting an α particle. The next two nuclides in the series emit β⁻ particles.

What nuclide is formed after these three decays have taken place?

• 
• 
• 
• 

Tags

NGSS.HS-PS1-8

Which sequence of radioactive emissions results in the formation of an isotope of the original element?

• one α particle and one β⁻ particle

• one α particle and two β⁻ particles

• two α particles and one β⁻ particle

• two α particles and two β⁻ particles

Tags

NGSS.HS-PS1-8

A radioactive nucleus emits a β^–. particle then an α particle and finally another β^–. particle. The final nuclide is

• an isotope of the original element

• the same element with a different proton number

• a new element of higher proton number

• a new element of lower nucleon number

Tags

NGSS.HS-PS1-8

A nucleus of a particular element decays, emitting a series of α and β⁻ particles.

Which of the following series of emissions would result in an isotope of the original element?

• 1 α and 1 β⁻

• 1 α and 2 β⁻

• 2 α and 1 β⁻

• 2 α and 2 β⁻

Tags

NGSS.HS-PS1-8