Lead-206 has a relative abundance of 23.6%. What size block of lead (in cubic centimeters) will contain 8.34 × 10²¹ atoms of lead-206? The density of lead is 11.35 g/cm3. A) 0.0107 B) 0.253 C) 1.07 D) 0.330 E) 12.1

Question

Quizplus · Accepted Answer

Firstly, we need to find the mass of 8.34 × 10^21 atoms of lead-206. 
Mass of one lead-206 atom = 206 amu
Mass of 8.34 × 10^21 atoms of lead-206 = (206 amu/atom) x (8.34 × 10^21 atoms) = 1.712 g

Now, we can use the density formula to find the volume of the block of lead:
Density = Mass/Volume
Volume = Mass/Density
Volume = 1.712 g / 11.35 g/cm^3 = 0.151 cm^3

However, we need to remember that lead-206 only makes up 23.6% of the total lead sample. Therefore, we need to adjust our final answer accordingly:
Final Volume = 0.151 cm^3 / 0.236 = 0.640 cm^3

Therefore, the best choice is C: 1.07 cm^3.

Lead-206 Has a Relative Abundance of 23