In the determination of the specific heat of a metal, why is it desirable to use the minimum volume of water that will allow immersion of the metal sample? 14

Because it will allow a bigger temperature change.

Explanation:

The specific heat of the metal can be calculated by the heat change between it and the water. The total amount of heat must be 0, thus, the heat of the metal (Qm) plus the heat of water (Qw):

Qm + Qw = 0

The heat is the mass multiplied by the specific heat (c) and by the temperature change:

mm*cm*ΔTm + mw*cw*ΔTw = 0

mm*cm*ΔTm = - mw*cw*ΔTw

So, as higher is the value of mw, as low is the value of ΔTw, and if ΔTw is very low, and so the calculations may not be precise.