Question

What is the volume V of a sample of 4.00 mol of copper? The atomic mass of copper (Cu) is 63.5 g/mol, and the density of copper is 8.92 x 10^3kg/m^3. Express your answer in cubic centimeters to 3 significant figures.

Answer 1

Answer : The volume of a sample of 4.00 mol of copper is $28.5cm^3$

Explanation :

First we have to calculate the mass of copper.

$\text{ Mass of copper}=\text{ Moles of copper}\times \text{ Molar mass of copper}$

$\text{ Mass of copper}=(4.00moles)\times (63.5g/mole)=254g$

Now we have to calculate the volume of copper.

Formula used :

$Density=\frac{Mass}{Volume}$

Now put all the given values in this formula, we get:

$8.92\times 10^3kg/m^3=\frac{254g}{Volume}$

$Volume=\frac{254g}{8.92\times 10^3kg/m^3}=2.85\times 10^{-2}L=2.85\times 10^{-2}\times 10^3cm^3=28.5cm^3$

Conversion used :

$1kg/m^3=1g/L\\\\1L=10^3cm^3$

Therefore, the volume of a sample of 4.00 mol of copper is $28.5cm^3$

Answer 2

Answer:$V=28.4\times 10^{-6} m^3$

Explanation:

Given

no of moles=4

Atomic mass of copper=63.5 g/mol

Density of copper$=8.92\times 10^3 kg/m^3$

no of moles$=\frac{mass of copper}{Atomic weight}$

$4=\frac{mass}{63.5}$

mass=254 gm

and $mass=density\times volume$

$254\times 10^{-3}=8.92\times 10^3\times V$

$V=\frac{254\times 10^{-3}}{8.92\times 10^3}$

$V=28.4\times 10^{-6} m^3$