Neco Model Questions Vol1 2022 Physics Question 1

Practice objective / multiple choice question 1 from the 2022 Neco Model Questions Vol1 Physics examination.

Neco Model Questions Vol1 2022 Physics Objective / Multiple Choice Hard Difficulty
Question 1 NECO_MODEL_QUESTIONS_VOL1 • 2022 • PHYSICS • objective

A 5.0 g mixture of two radioactive isotopes, A (half‑life 30 min, decays 100 % to daughter C) and B (half‑life 2 h, decays 80 % to C and 20 % to a stable nuclide D), is prepared. After exactly 3 h the activity of daughter C is measured as \(1.0\times10^{17}\) Bq. The atomic masses are 240 u for A and 238 u for B. Assuming each decay that produces C contributes one count to the activity, determine the initial mass of isotope A in the mixture (in grams, to two decimal places).

Answer Options

A. 3.12 g
Correct Answer B. 4.55 g
C. 5.67 g
D. 2.98 g
Correct Answer
B
Correct Option:
4.55 g

About This Question

This is Neco Model Questions Vol1 2022 Physics Question 1. It is one of the objective questions from the 2022 Neco Model Questions Vol1 Physics examination.

Difficulty level: Hard .

Master the Exam!

You've seen a preview, but there are thousands more questions plus AI tutor to break down complex solutions.

Unlock Full Access Available for Android & Windows
Chat with Support