CIE iGCSE Co-Ordinated Science P5.2.1 Detection of radioactivity Exam Style Questions Paper 1
Question
A radioactive nucleus emits a β-particle. What happens to the proton number (atomic number) of the nucleus?
A. It stays the same.
B. It increases by 1.
C. It decreases by 2.
D. It decreases by 4.
▶️Answer/Explanation
Answer: B
Explanation: When a β-particle (electron) is emitted, a neutron in the nucleus is converted into a proton, increasing the atomic number by 1.
Question
A radioactive material has a half-life of 4.0 days. The rate of emission of radiation from a sample of the material is 32 emissions per minute.
What was the rate of emission from the sample 8.0 days earlier?
(A) 8.0 emissions per minute
(B) 128 emissions per minute
(C) 256 emissions per minute
(D) 1024 emissions per minute
▶️Answer/Explanation
Ans: B