Alkene (X) `(C_(5)H_(10))` on ozonolysis gives a mixture of two compounds (Y) and (Z). Compound (Y) gives positive Fehling's test and iodoform test. Compound (Z) does not give Fehling's test but give iodoform test. Name the compound formed when Z reacts with Mg - Hg / `H_(2)O`

Answer

To solve the question step by step, we will analyze the information given and deduce the required compounds and their reactions.

### Step 1: Identify the compounds Y and Z from the ozonolysis of alkene (X)
- The alkene (X) has the formula \(C_5H_{10}\).
- Upon ozonolysis, it produces two compounds (Y and Z).
- Compound (Y) gives a positive Fehling's test and an iodoform test, indicating that it is an aldehyde with a ketomethyl group (a methyl group adjacent to a carbonyl group).
- Compound (Z) does not give a Fehling's test but gives an iodoform test, indicating that it is a ketone with a ketomethyl group.

### Step 2: Determine the structure of compound Y
- Since Y is an aldehyde and gives a positive iodoform test, it must be an aldehyde with a structure that includes a ketomethyl group.
- The simplest structure that fits this description is **butanal** (an aldehyde with four carbons) and a methyl group adjacent to the carbonyl, which gives us **3-pentanone**.

### Step 3: Determine the structure of compound Z
- Compound Z is a ketone that gives a positive iodoform test. The only ketone that fits this description and has a ketomethyl group is **acetone** (which is 2-propanone).

### Step 4: Write the ozonolysis reaction
- The ozonolysis of the alkene (X) leads to:
- Y: 3-pentanone (C4H8O)
- Z: Acetone (C3H6O)

### Step 5: Identify the reaction of compound Z (acetone) with Mg-Hg/H2O
- When acetone reacts with magnesium amalgam (Mg-Hg) in the presence of water, it undergoes a reduction reaction known as the **pinacol reaction**, leading to the formation of **pinacol**.
- The reaction can be summarized as:
\[ 2 \text{acetone} \xrightarrow{\text{Mg-Hg/H}_2\text{O}} \text{pinacol} \]

### Step 6: Name the compound formed
- The compound formed from the reaction of acetone with Mg-Hg/H2O is **pinacol**.
- The IUPAC name of pinacol is **2,3-dimethyl-2,3-butanediol**.

### Final Answer
The compound formed when Z (acetone) reacts with Mg-Hg/H2O is **pinacol**, or its IUPAC name is **2,3-dimethyl-2,3-butanediol**.

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