CIE iGCSE Co-Ordinated Science P5.2.3 Radioactive decay Exam Style Questions Paper 2
Question
A uranium nucleus decays into a thorium nucleus. The thorium nucleus then decays into a protactinium nucleus.
$_{238}^{92}\textrm{U}\to _{234}^{90}\textrm{Th}\to _{234}^{91}\textrm{Pa}$
Which emissions take place during the decays?
(A) an alpha-particle followed by a beta-particle
(B) an alpha-particle followed by another alpha-particle
(C) a beta-particle followed by an alpha-particle
(D) a beta-particle followed by another beta-particle
▶️Answer/Explanation
Ans: A
Question
A uranium nucleus decays by emitting an alpha (∝)-particle. The nuclide equation shows this
decay.
\( _{92}^{X}\textrm{U} \to _{234}^{Y}\textrm{Th}\) + ∝-particle
What are the numbers X and Y?
▶️Answer/Explanation
Ans: C
Question
A nucleus of carbon \(_{6}^{14}\textrm{C}\) decays by beta (β–)-emission to an isotope of nitrogen N. What is the nuclide of nitrogen formed?
(A) \(_{4}^{10}\textrm{N}\)
(B) \(_{5}^{14}\textrm{N}\)
(C) \(_{7}^{14}\textrm{N}\)
(D) \(_{7}^{15}\textrm{N}\)
▶Answer/Explanation
Ans : C
Question
A radioactive nucleus \(_{92}^{238}\textrm{U}\) decays into a thorium (Th) nucleus by emitting an alpha-particle.
What is the symbol for the thorium nucleus formed?
A \(_{90}^{234}\textrm{Th}\)
B \(_{92}^{234}\textrm{Th}\)
C \(_{90}^{238}\textrm{Th}\)
D \(_{92}^{238}\textrm{Th}\)
▶️Answer/Explanation
Ans : A