Which One of the Following Pairs of Substances Could Be

question 77

Multiple Choice

Which one of the following pairs of substances could be used to construct a single redox electrode (i.e., they have an element in common, but in different oxidation states) ?

• A)HCl and Cl ⁻
• B)H ⁺ and OH ⁻
• C)H ₂O and H ⁺
• D)Fe ³⁺ and Fe ₂O ₃
• E)MnO ₂ and Mn ²⁺

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Definitions:

PO

An abbreviation for "per os," a latin term meaning "by mouth," used in medical prescriptions.

Tablets

Portable, touchscreen computing devices that are larger than smartphones but smaller than laptops.

Triazolam

A benzodiazepine used to treat insomnia by decreasing the time to fall asleep.

PO HS

An abbreviation in medical prescriptions indicating that the medication should be taken orally (PO) at bedtime (HS).