A Tiny Speck (2

question 8

Multiple Choice

A tiny speck (2.0 * 10^-4 g) of radioactive americium-241 (241.06 g/mol) is used in smoke detectors. How many atoms of americium-241 are there in one of these smoke detectors?

• A) 5.0 * 10¹⁷ atoms
• B) 1.2 * 10²⁰ atoms
• C) 2.9 * 10²² atoms
• D) 6.0 * 10²³ atoms
• E) 8.3 * 10⁷ atoms