At a temperature of 100^ circ C, Copper (Cu) exhibits an FCC structure with an edge length of xtext AA . What is the approximate density of Copper in text g cm ^ -3 at this state? (Atomic Mass of Cu = 63.55text u )

Home › MCQs › EEJ MAIN Chemistry › Question #7141

EEJ MAIN Chemistry QUESTION #7141

Question 1

At a temperature of $100^{\circ}C$, Copper ($Cu$) exhibits an FCC structure with an edge length of $x\text{ \AA}$. What is the approximate density of Copper in $\text{g cm}^{-3}$ at this state? (Atomic Mass of $Cu = 63.55\text{ u}$)

$\frac{205}{x^{3}}$
$\frac{105}{x^{3}}$
$\frac{422}{x^{3}}$
$\frac{211}{x^{3}}$✔️

Correct Answer Explanation

The density ($d$) formula is $d = \frac{Z \times M}{N_A \times a^3}$.

For an FCC lattice, $Z = 4$.
$M = 63.55\text{ g/mol}$.
$a = x\text{ \AA} = x \times 10^{-8}\text{ cm}$.
$N_A \approx 6.022 \times 10^{23}$.

Calculation: $d = \frac{4 \times 63.55}{6.022 \times 10^{23} \times (x \times 10^{-8})^3} \approx \frac{254.2}{0.6022 \times x^3} \approx \frac{422}{x^3}$.

More Options