Question

The Statue of Liberty is made of $2.0\times {10}^5$ lbs of copper sheets bolted to a framework $(1lb=454g)$. How many atoms of copper are there on the statue?

(Atomic weight: $Cu=63.5$).

• A. $2.1\times {10}^{27}$
• B. $8.6\times {10}^{29}$
• C. $4.3\times {10}^{26}$
• D. $8.6\times {10}^{26}$

Answer 1

Answer: (B)

$8.6\times {10}^{29}$

Given,

mass of copper $=2\times {10}^{5}lbs$

$=2\times {10}^5\times 454g$

Molecular wt. of copper $=63.5g/moles$

$\therefore$ No. of moles of copper $=\frac{2\times {10}^5\times 454}{63.5}$

Thus, no. of atoms of copper on the statue

$=\frac{2\times {10}^5\times 454}{63.5}\times 6.023\times {10}^{23}$

$=8.6\times {10}^{29}$ atoms

Hence, the correct option is (B)