If a 20 wt Sn alloy is cooled from the liquid state the firs

If a 20 wt% Sn alloy is cooled from the liquid state, the first solid phase to form is Composition (at% Sn) 20 60 100 327 C 600 300 500 200 400 183°C 18.3 1.9 97.8 300 100 200 100 40 60 100 (Pb) Composition (wt% Sn) (Sn) 0.0+ phases, 18.3 wt96 Sn and 97.8wt96 Sn at 1830C \"a phase that is 7wt% Sn at 300°C \'a phase that is 10 wt% Sn at 280°C o None of the above o\"B phase that is 98wt% Sn at 200°C

Solution

ANSWER FOR THE ABOVE QUESTION IS

A) ALPHA + BETA PHASES, 18.3 WT% Sn AND 97.8% Sn AT 183\'C

IF WE WANT TO CALCULATE THE MASS FRACTION OF THIS PHASE WE MUST USE LEVER RULE.