5.01 lb mass 66% copper 6.304×10^(-3) in 8.95 g/cm3

5.01 lb mass 66% copper 6.304×10^(-3) in 8.95 g/cm3

 

 

Copper can be drawn into thin wires. How many meters of 34-gauge wire (diameter = 6.304×10^(-3) in) can be produced from copper in 5.01 lbs of covellite, an ore of copper that is 66% Cu by mass?

(Hint: Treat the wire as a cylinder; V of cylinder = πr^2h; d of copper = 8.95 g/cm3)

 

 

 

(5.01 lb) (453.59237 g / 1 lb) = 2272.498 g covellite

 

2272.498 g × (66/100) = 1499.849 g Cu

 

 

 

밀도 = 질량 / 부피 이므로,

부피 = 질량 / 밀도

= 1499.849 g / (8.95 g/cm3)

= 167.58 cm3 Cu

 

 

 

(6.304×10^(-3) in) (2.54 cm / 1 in) = 0.016012 cm

 

V = πr^2h 이므로,

h = V / πr^2

= (167.58 cm3) / [π × (0.016012 / 2 cm)^2]

= 832225.7 cm

= 8322 m

 

 

 

답: 8.3×10^3 m

 

 

 

 

[키워드] covellite 기준