Sodium salts of carboxylic acids on heating with soda lime give

Options

A. alkene
B. alkanes
C. ethene
D. benzene

Answer

To solve the question regarding the reaction of sodium salts of carboxylic acids when heated with soda lime, we can break it down into the following steps:

### Step 1: Understand the Reactants
Sodium salts of carboxylic acids are typically represented as RCOONa, where R is an alkyl or aryl group. Soda lime is a mixture of sodium hydroxide (NaOH) and calcium oxide (CaO).

### Step 2: Identify the Reaction Type
The reaction that occurs when sodium salts of carboxylic acids are heated with soda lime is known as decarboxylation. This process involves the removal of a carboxyl group (-COOH) from the carboxylic acid, resulting in the formation of an alkane.

### Step 3: Write the General Reaction
The general reaction can be represented as follows:
\[ RCOONa + \text{Soda Lime} \xrightarrow{\text{heat}} RCH_3 + Na_2CO_3 \]
Here, RCH3 represents the alkane formed after the decarboxylation.

### Step 4: Example Reaction
For a specific example, consider sodium acetate (CH3COONa):
\[ CH_3COONa + \text{Soda Lime} \xrightarrow{\text{heat}} CH_4 + Na_2CO_3 \]
In this reaction, sodium acetate is converted into methane (CH4) and sodium carbonate (Na2CO3).

### Step 5: Conclusion
Thus, the sodium salts of carboxylic acids, when heated with soda lime, yield alkanes and sodium carbonate.

### Final Answer
Sodium salts of carboxylic acids on heating with soda lime give alkanes (specifically, one carbon less than the original carboxylic acid) and sodium carbonate.

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