The Cu²⁺ Ion Can Be Separated from Ag⁺,Ca²⁺,and K⁺ in Aqueous

question 65

Multiple Choice

The Cu²⁺ ion can be separated from Ag⁺,Ca²⁺,and K⁺ in aqueous solution by

• A)precipitation of Cu²⁺ as CuS(s)at pH-1.
• B)precipitation of Cu²⁺ as Cu(OH)₂(s)with 6 M NaOH(aq).
• C)precipitation of Cu²⁺ as CuCl₂(s)with 6 M HCl(aq).
• D)precipitation of Ag⁺,Ca²⁺,and K⁺ as the carbonates.
• E)None of these procedures will separate Cu²⁺ from the other ions.

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Definitions:

Hertz

The unit of frequency in the International System of Units (SI), equal to one cycle per second.

Absolute Threshold

The smallest quantity of a stimulus that an individual can detect.

Difference Threshold

The minimal change in a stimulus that can just barely be detected by an organism.

Difference Threshold

The minimum difference in stimulation that a person can detect 50% of the time, also known as the "just noticeable difference" (JND).