You Are Working on a Project to Recycle Nickel and Cadmium

question 62

Multiple Choice

You are working on a project to recycle nickel and cadmium from old nickel-cadmium batteries that have an iron casing.The batteries are dissolved in aqueous nitric acid, producing a solution containing primarily Ni²⁺, Cd²⁺, and Fe³⁺ cations.One idea is to add sodium hydroxide to neutralize the acid and cause precipitation of Ni(OH) ₂, Cd(OH) ₂, and Fe(OH) ₃.Assume the concentration of each of the cations is 0.100 M before the sodium hydroxide is added.The pH increases as the sodium hydroxide is added.Which compound will precipitate first, and what is the pH at that point?

• A)Cd(O
• H)₂; pH = 9.16
• B)Fe(O
• H)₃; pH = 4.81
• C)Fe(O
• H)₃; pH = 1.93
• D)Cd(O
• H)₂; pH= 6.42
• E)Ni(O
• H)₂; pH =7.24

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Definitions:

Sphenoid Bone

A complex, butterfly-shaped bone at the base of the skull, which forms part of the eye socket, the nasal cavity, and the floor of the cranium.

Temporal Bone

A bone situated at the sides and base of the skull, containing the structures of the ear.

Sternum

A flat bone located in the center of the chest, serving as a major attachment point for ribs and protecting vital chest organs.

Axial

The term axial refers to positions, structures, or movements that are situated around, or part of, the central axis of the body or an organ.