A magnesium–lead alloy of mass 7.5 kg consists of a solid a phase that has a composition just slightly below the solubility limit at 300°C (570°F). (a) What mass of lead is in the alloy? (b) If the...

A magnesium–lead alloy of mass 7.5 kg consists of a solid a phase that has a composition just slightly below the solubility limit at 300°C (570°F). (a) What mass of lead is in the alloy? (b) If the alloy is heated to 400°C (750°F), how much more lead may be dissolved in the a phase without exceeding the solubility limit of this phase?