Identify W, X, Y and Z respectively in the given reactions.
`CaCO_(3)overset(Delta)toW+X`
`W+H_(2)O to Y`
`Y+Z to NaOH+CaCO_(3)`

Options

A. `CaO,CO_(2),CaCO_(3),Na_(2)CO_(3)`
B. `CO_(2),Ca(OH)_(2),Ca(HCO)_(3),NaHCO_(3)`
C. `CaO,CO_(2),Ca(OH)_(2),Na_(2)CO_(3)`
D. `CO_(2),CaO,H_(2)CO_(3),Na_(2)CO_(3)`

Explanation

To solve the problem, we need to identify the substances W, X, Y, and Z in the given reactions involving calcium carbonate (CaCO₃). Let's break down the reactions step by step.

### Step 1: Identify W and X from the first reaction
The first reaction is:
\[ \text{CaCO}_3 \overset{\Delta}{\rightarrow} W + X \]

When calcium carbonate (CaCO₃) is heated (denoted by Δ), it decomposes into calcium oxide (CaO) and carbon dioxide (CO₂). Therefore, we can identify:
- **W = CaO**
- **X = CO₂**

### Step 2: Identify Y from the second reaction
The second reaction is:
\[ W + H_2O \rightarrow Y \]

Substituting W from the previous step:
\[ \text{CaO} + H_2O \rightarrow Y \]

When calcium oxide (CaO) reacts with water (H₂O), it forms calcium hydroxide (Ca(OH)₂). Thus, we identify:
- **Y = Ca(OH)₂**

### Step 3: Identify Z from the third reaction
The third reaction is:
\[ Y + Z \rightarrow \text{NaOH} + \text{CaCO}_3 \]

Substituting Y from the previous step:
\[ \text{Ca(OH)}_2 + Z \rightarrow \text{NaOH} + \text{CaCO}_3 \]

To produce sodium hydroxide (NaOH) and calcium carbonate (CaCO₃), Z must be sodium carbonate (Na₂CO₃). Therefore, we identify:
- **Z = Na₂CO₃**

### Summary of Identifications:
- **W = CaO**
- **X = CO₂**
- **Y = Ca(OH)₂**
- **Z = Na₂CO₃**

### Final Answer:
W = CaO, X = CO₂, Y = Ca(OH)₂, Z = Na₂CO₃