The Newman projection formula of most stable sonformation 3- Hydroxypropanal is gauche. It is stable due to

Answer

To solve the question regarding the stability of the gauche conformation of 3-hydroxypropanal, we will follow these steps:

### Step 1: Identify the Structure of 3-Hydroxypropanal
3-Hydroxypropanal has the molecular formula C3H6O2. The structure consists of a propanal (an aldehyde) with a hydroxyl (-OH) group on the third carbon. The structural formula can be represented as:
```
CHO
|
CH
|
CH2OH
```

### Step 2: Understand the Newman Projection
The Newman projection is a way to visualize the conformation of a molecule by looking down the bond between two carbon atoms. For 3-hydroxypropanal, we will consider the conformation around the carbon-carbon bond between the second and third carbons.

### Step 3: Draw the Gauche Conformation
In the gauche conformation, the substituents on the two carbons are staggered, and we can visualize it as follows:
```
H OH
\ /
C
/ \
H CHO
```
Here, the hydroxyl group (OH) on the third carbon is adjacent to the aldehyde group (CHO) on the first carbon.

### Step 4: Analyze the Stability
The stability of the gauche conformation arises from the interactions between the functional groups. In this case, the hydroxyl group (OH) can form a hydrogen bond with the carbonyl group (C=O) of the aldehyde. This intramolecular hydrogen bonding stabilizes the molecule.

### Step 5: Conclusion
The most stable conformation of 3-hydroxypropanal is the gauche form, and it is stable due to intramolecular hydrogen bonding between the hydroxyl group and the carbonyl group.

### Final Answer
The gauche conformation of 3-hydroxypropanal is stable due to intramolecular hydrogen bonding between the hydroxyl group and the carbonyl group.

---