A solid cylinder of pure aluminum (Sample D) has a mass of 270 g and a volume of 100 cm
CHEMISTRY · Multi-part · AP · Chemistry · Compound Structure and Properties · Compound Structure and Properties
Problem
A solid cylinder of pure aluminum (Sample D) has a mass of 270 g and a volume of 100 cm3. An identical-sized cylinder of the alloy duralumin (Sample E, nominal composition 94 % Al, 4 % Cu, 1 % Mg, 1 % Mn by mass) has a mass of 290 g.
Additional information (at 25 °C):
• Resistivity of pure Al = 2.65μΩ⋅cm
• Resistivity of duralumin = 3.20μΩ⋅cm
(a) Calculate the density of the pure aluminum cylinder in g cm−3.
(b) Calculate the density of the duralumin cylinder in g cm−3.
(c) Compare the two densities and explain the difference in terms of atomic size and the type of alloy formed.
(d) Using the resistivity data, determine which cylinder conducts electricity better and provide a molecular-level explanation for the observed difference.