Question

What does the unit "Becquerel (Bq)" define?

• A. The activity of a pathogenic material.
• B. The activity of a radio-active material.
• C. The activity of a chemical material.
• D. A hardness of material.

Hint:

Associate units with their quantities:

\textbf{Becquerel (Bq)} or \textbf{Curie (Ci)} $\rightarrow$ Radioactivity.
\textbf{Gray (Gy)} or \textbf{Rad} $\rightarrow$ Absorbed dose of radiation.
\textbf{Sievert (Sv)} or \textbf{Rem} $\rightarrow$ Equivalent dose (biological effect) of radiation.

Answer 1

The Correct Option is B

Step 1: Define the Becquerel unit. Step 1: The Becquerel (Bq) is the SI unit for radioactivity.
Step 2: Connect the definition to the choices.
Step 2: One Becquerel represents one nuclear decay per second. This directly corresponds to the activity of a radioactive substance.
Step 3: Discard incorrect choices.
Step 3:

Pathogenic activity concerns disease-causing capability; it is not measured in Bq.
Chemical activity is quantified by reaction rates or concentration (e.g., moles per liter).
Hardness is a physical attribute measured on scales such as Mohs or Vickers.
Consequently, the only correct selection is (B).