A chemist investigates a two-stage displacement–precipitation sequence designed to…
CHEMISTRY · Multi-part · AP · Chemistry · Chemical Reactions · Chemical Reactions
Problem
A chemist investigates a two-stage displacement–precipitation sequence designed to remove copper from industrial waste.
Step 1 A strip of zinc metal is immersed in 250 mL of 0.10 M CuSO₄(aq) until the blue color disappears.
Step 2 After the strip is removed and excess solid copper is filtered off, solid Na₂CO₃ is added in small portions to the remaining filtrate until no further solid forms.
Ignore any acid–base reactions of CO₂ with water, and assume the solution remains open to the atmosphere.
(a) Write the net ionic equation for each step.
(b) Combine the two equations from part (a) to obtain the overall net ionic equation for the sequence.
(c) Calculate the theoretical mass, in grams, of the final solid product formed in step 2 if the strip originally had a mass of 2.50 g. Assume the zinc strip is in large excess.
(d) Identify the oxidation states of all metallic species before and after the sequence, and state whether each step is classified as a redox process, a precipitation process, or both.