Answer:
(a). 5.4 × 10^23 atoms.
(b). 0.8928 moles Ni.
Explanation:
The first thing to do is to convert surface area from the in^2 to cm^2 and also the thickness unit to cm.
Therefore, 200 in^2 = 1290.3 cm^2 and 0.002 in = 0.00508 cm.
The next thing to do is to calculate the volume by using the formula below;
Volume= A × d. Where A = area and d = thickness.
Then, volume = 1290.3 × 0.00508= 6.55 cm^3.
Although not given but the Density if Nickel = 8 g/cm^3.
We know that the formula for Calculating density = mass / volume. So, we have ; mass = density × volume.
Mass= 8 × 6.55 = 52.4 g.
(a). The number of atoms of Nickel= moles × Avogrado's number.
Numbers of moles= mass / molar mass.
==> 52.4 / 58.6934 = 0.8928 moles.
Then, the number of atoms of Nickel = 0.8928 × 6.02 × 10^23.
= 5.4 × 10^23 atoms.
(b). The number of moles of Nickel has been Calculated in (a) above to be = 0.8928 moles Ni.
