Answer:
The concentration of Li (in wt%) is 3,47g/mol
Explanation:
To obtain the 2,42g/cm³ of density:
2,42g/cm³ = 2,71g/cm³X + 0,534g/cm³Y <em>(1)</em>
<em>Where X is molar fraction of Al and Y is molar fraction of Li.</em>
X + Y = 1 <em>(2)</em>
Replacing (2) in (1):
Y = 0,13
Thus, X = 0,87
The weight of Al and Li is:
0,87*26,98g/mol = 23,4726 g of aluminium
0,13*6,941g/mol = 0,84383 g of lithium
The concentration of Li (in wt%) is:
0,84383g/(0,84383g+23,4726g) ×100= <em>3,47%</em>