CAIE IGCSE Physics 5.2.3 Radioactive Decay

Covered syllabus points

5.2.3.1—Radioactive decay is a change in an 5.2.3.2—During α-decay or β-decay, the nucleus 5.2.3.3—Isotopes of an element may be 5.2.3.4—Effect of α-decay, β-decay and 5.2.3.5—Decay equations, using nuclide

[Maximum number: 1]

The nuclei of the atoms in a substance are changing randomly and emitting radiation.
What is happening to the substance?

It is undergoing electromagnetic induction.

It is undergoing magnetisation.

It is undergoing solidification.

It is undergoing radioactive decay.

[Maximum number: 1]

Which row correctly describes an example of radioactive decay?

original
nucleus

emission

change or
no change of element

stable

$\gamma$

change of element

unstable

$\alpha$

change of element

unstable

$\alpha$

no change of element

unstable

$\beta$

no change of element

[Maximum number: 4]

The isotope thallium-208 $\left({ }_{81}^{208} \mathrm{~T} l\right)$ is radioactive. It decays by $\beta$ -decay.

(a)

Thallium-208 decays to an isotope of lead (Pb).

[ 4 ]

(i)

Complete the equation for this decay.

{ }_{81}^{208} \mathrm{Tl} \longrightarrow{ }_{\cdots \cdots \cdots}^{\cdots \cdots \cdots} \mathrm{Pb}+{ }_{\ldots \cdots \cdots}^{\cdots \cdots \cdots} \beta

[ 3 ]

${ }_{-1}^{0} \beta$

Figure for Answer to Question (i) — CAIE IGCSE Physics

... $_{82} \mathrm{~Pb}$

(ii)

Suggest one reason why a nucleus of thallium-208 is unstable.

[ 1 ]

[Maximum number: 1]

The isotope thallium-208 $\left({ }_{81}^{208} \mathrm{~T} l\right)$ is radioactive. It decays by $\beta$ -decay.

Thallium-208 decays to an isotope of lead (Pb).

Suggest one reason why a nucleus of thallium-208 is unstable.

[Maximum number: 1]

A source contains a radioactive isotope of strontium. This isotope decays by emission of $\beta$ -particles. The half-life of this isotope is 29 years.

State the change in the nucleus which occurs when a $\beta$ -particle is emitted.

(in the nucleus a) neutron is changed into a proton (and an electron which is the emitted $\beta$ -particle)

[Maximum number: 3]

Sodium-24 is an isotope of sodium (Na) that has a proton number of 11 and a nucleon number of 24.

Sodium-24 decays by emission of a beta-particle to form an isotope of magnesium (Mg).
Use nuclide notation to write down the nuclide equation for this decay.

${ }_{11}^{24} \mathrm{Na} \rightarrow{ }_{12}^{24} \mathrm{Mg}+{ }_{-1}^{0} \beta$ ${ }_{11}^{24} \mathrm{Na}$ on LHS
${ }_{-1}^{0} \beta$ on RHS
${ }_{12}^{24} \mathrm{Mg}$ on RHS

All question bank results loaded

CAIE IGCSE Physics 5.2.3 Radioactive Decay Topic Practice

Covered syllabus points

Question 1

Question 2

Question 3

Question (a)

Question (i)

Question (ii)

Question 4

Question 5

Question 6