Which of the following compounds is produced when lithium metal (Li) undergoes combustion in oxygen?

• A. Li2CO3
• B. LiO2
• C. Li2O
• D. LiOH

Answer: (C)

Verified step by step guidance

1. Step 1: Understand the reaction type. Combustion of a metal like lithium in oxygen typically forms a metal oxide, where lithium reacts directly with oxygen gas (O\_2).
2. Step 2: Write the general combustion reaction for lithium: \$4\ Li + O\_2 \rightarrow 2\ Li\_2O$. This shows lithium combining with oxygen to form lithium oxide.
3. Step 3: Analyze the given options. Lithium carbonate (Li\_2CO\_3) and lithium hydroxide (LiOH) contain additional elements (carbon and hydrogen, respectively) that are not part of a simple combustion reaction with oxygen alone.
4. Step 4: Consider lithium superoxide (LiO\_2). This is a less common product and typically forms under specific conditions, not the straightforward combustion of lithium metal in oxygen.
5. Step 5: Conclude that the most straightforward and common product of lithium combustion in oxygen is lithium oxide (Li\_2O), matching the balanced reaction and typical chemical behavior.