Find Work done by block of gold?

AI Thread Summary
To find the work done by a block of gold when heated from 20°C to 1064°C, the density of solid gold is 19.3 g/cm3 and that of liquid gold is 17.3 g/cm3. The mass of the gold block is 407 kg, and the volume must be calculated at both temperatures using the formula v = m/p. The initial attempt at calculating work using the pressure-volume work equation W = -pΔV was incorrect due to an error in determining ΔV. It is recommended to first convert all units to kg and kg/m3 for accurate calculations before proceeding with the work formula.
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Homework Statement


The density of solid gold at 20°C is
ρ = 19.3 g/cm3.
When it is liquid at 1064°C the density of the liquid state is decreased: 17.3 g/cm3. How much work does a block of gold of mass 407 kg do if it is heated at
p = 1.0 atm
from 20°C to 1064°C?

Homework Equations


density=mass/volume
PV=nRT
W=-pdeltaV


The Attempt at a Solution


I started by taking difference between two pressures =2.0g/cm3 and then converted that to 2000kg/cm3. with this i used
p=m/v
v=m/p
v=407kg/2000kg/m3
v=0.2035m3 =203.5L
W=-pdeltaV
W=1.0atm(203.5L)
W= 203.5atm.L=20619 J
this does not seem correct at all and it isn't.
 
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I believe you haven't worked out ΔV correctly. Start by working out the volume at the two different temperatures. Perhaps best to convert the data given in the question to kg and kg/m3 first.
 

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