Answer:
A is denser than B as it's volume for the same mass is smaller.
Explanation:
Hello.
In this case, we first need to take into account that the density of each metal A and B is computed by dividing the mass over the volume of each metal which is actually computed by substracting the volume of water from the volume of the water and the solid:

Next, we compute the densities as shown below:

In such a way, A is denser is B as it's volume for the same mass is smaller.
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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
<u>Answer:</u> The molality of solution is 0.740 m.
<u>Explanation:</u>
To calculate the mass of solvent (water), we use the equation:

Volume of water = 750 mL
Density of water = 1 g/mL
Putting values in above equation, we get:

To calculate the molality of solution, we use the equation:

Where,
= Given mass of solute
= 100.0 g
= Molar mass of solute
= 180 g/mol
= Mass of solvent (water) = 750 g
Putting values in above equation, we get:

Hence, the molality of solution is 0.740 m.