How many moles of `PbCO_3` are present in whitelead ?

Explanation

To determine how many moles of PbCO3 (lead carbonate) are present in white lead, we can follow these steps:

### Step 1: Understand the Composition of White Lead
White lead is a compound that consists of lead carbonate and lead hydroxide. The chemical formula for white lead is given as:
\[ \text{2PbCO}_3 \cdot \text{Pb(OH)}_2 \]

### Step 2: Identify the Components
From the formula, we can see that white lead contains:
- 2 moles of PbCO3 (lead carbonate)
- 1 mole of Pb(OH)2 (lead hydroxide)

### Step 3: Determine the Moles of PbCO3
Since the formula indicates that there are 2 moles of PbCO3 in the composition of white lead, we can conclude that:
\[ \text{Moles of PbCO}_3 = 2 \]

### Final Answer
Thus, the number of moles of PbCO3 present in white lead is:
\[ \text{2 moles} \]

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