Cherylyn L. answered 09/24/19
PhD in Chemistry with 10 years of Tutoring and Teaching Experience
I believe this problem is asking for how many meters of COPPER wire with... can be produced from...
You are asked for the length of wire with a specific diameter, and you can think of this as solving for the height of a very tall cylinder (the wire).
First you need to know how much copper you will have (from the mineral) to make the wire:
45.3% of 3.54 lbs dioptase is copper, so 0.453 x 3.54 lbs = 1.60 lbs Cu
Use dimensional analysis to convert the Cu mass from lbs to g using the equivalent you would look up,
1 lb = 454 g
1.60 lbs x 454 g/ 1 lb = 726.4 g
Use the density of Cu (look up) to convert the Cu mass to volume:
density of Cu is 8.96 g/cm3 or 8.96 g = 1 cm3 ; 726.4 g x 1 cm3/ 8.96 g = 81.1 cm3
So the volume of the cylinder (wire) is 81.1 cm3, volume of a cylinder is V = πr2h. You are given the diameter, 0.0571 in, so you can determine the radius (1/2 diameter) is 0.0571 in/2 = 0.0286 in
Convert the radius from in to cm since volume is in cm3 using 1 in = 2.54 cm:
0.0286 in x 2.54 cm/ 1 in = 0.0725 cm
Rearrange V = πr2h to solve for h: h = V/πr2 = 81.1 cm3/ (π • (0.0725 cm)2) = 4910 cm
(divide both sides by πr2)
Convert your answer from cm to m: 4910 cm x 1 m/100 cm = 49.1 m Cu wire