Oxygen gas is not produced from the following decomposition reaction:

Options

A. `K_(2)Cr_(2)O_(7)overset(Delta)to`
B. `Ag_(2)C_(2)O_(4)overset(Delta)to`
C. `Pb(NO_(3))_(2)overset(Delta)to`
D. `Ag_(2)CO_(3)overset(Delta)to`

Explanation

To determine which decomposition reaction does not produce oxygen gas, we will analyze each given reaction step by step.

### Step 1: Analyze the decomposition of Potassium Dichromate (K2Cr2O7)

**Reaction:**
\[ K_2Cr_2O_7 \rightarrow K_2CrO_4 + Cr_2O_3 + O_2 \]

**Explanation:**
When potassium dichromate is heated, it decomposes to form potassium chromate, chromium(III) oxide, and oxygen gas. Therefore, this reaction does produce oxygen.

### Step 2: Analyze the decomposition of Silver Oxalate (Ag2C2O4)

**Reaction:**
\[ Ag_2C_2O_4 \rightarrow 2Ag + 2CO_2 \]

**Explanation:**
The decomposition of silver oxalate yields silver metal and carbon dioxide, with no oxygen gas produced. Thus, this reaction does not produce oxygen.

### Step 3: Analyze the decomposition of Lead Nitrate (Pb(NO3)2)

**Reaction:**
\[ 2Pb(NO_3)_2 \rightarrow 2PbO + 4NO_2 + O_2 \]

**Explanation:**
When lead nitrate decomposes, it produces lead(II) oxide, nitrogen dioxide, and oxygen gas. Hence, this reaction does produce oxygen.

### Step 4: Analyze the decomposition of Silver Carbonate (Ag2CO3)

**Reaction:**
\[ Ag_2CO_3 \rightarrow 2Ag + CO_2 + O_2 \]

**Explanation:**
The thermal decomposition of silver carbonate results in silver metal, carbon dioxide, and oxygen gas. Therefore, this reaction also produces oxygen.

### Conclusion

After analyzing all the reactions, we can conclude that the decomposition reaction that does not produce oxygen gas is the decomposition of silver oxalate (Ag2C2O4).

**Final Answer:**
The decomposition of silver oxalate (Ag2C2O4) does not produce oxygen gas.

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