When chemists stripped away oxygen from substances such as rocks and ore, what process were they performing?

• A. Oxidation
• B. Sublimation
• C. Hydrolysis
• D. Reduction

Answer: (D)

Verified step by step guidance

1. Understand the definitions of the key terms involved: Oxidation is the loss of electrons or an increase in oxidation state; Reduction is the gain of electrons or a decrease in oxidation state.
2. Recognize that when oxygen is removed from a substance, it means the substance is losing oxygen atoms, which corresponds to gaining electrons in the chemical sense.
3. Since gaining electrons is the hallmark of reduction, removing oxygen from substances like rocks or ores is an example of a reduction process.
4. Contrast this with oxidation, which involves adding oxygen or losing electrons, so removing oxygen cannot be oxidation.
5. Therefore, the process of stripping away oxygen from substances such as rocks and ores is called reduction.