Acopper-nickel alloy of composition 50 wt% ni-50 wt% cu is slowly heated from a temperature of 1200°c (2190 °f).
(a) at what temperature does the first liquid phase form?
(b) what is the composition of this liquid phase?
(c) at what temperature does complete melting of the alloy occur?
(d) what is the composition of the last solid remaining prior to complete melting?

nacl is added to the aqueous of what? ? in order to get a proper answer you have to specify the exact composition of the aqueous solution.

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