Answer:
0.1056 mole
Explanation:
As Sally knows that the charge on the metal ion is n = +2

In that compartment ![$[M^{n+}]=[m^{2+}]=8.279 \ M$](https://tex.z-dn.net/?f=%24%5BM%5E%7Bn%2B%7D%5D%3D%5Bm%5E%7B2%2B%7D%5D%3D8.279%20%5C%20M%24)
The volume of the
taken in that compartment = 6.380 mL
So, the number of moles of 
= 52.82 m mol
= 0.05280 mol

But n = 2
Therefore, moles of
= 2 x moles of 
= 2 x 0.05282
= 0.1056 mole
Alkali are soluble bases, however not all bases are soluble in water, therefore not all bases are Alkali.
Hey there!:
Volume in mL :
1.71 L * 1000 => 1710 mL
Density = 0.921 g/mL
Therefore:
Mass = Density * Volume
Mass = 0.921 * 1710
Mass = 1574.91 g