Which of following relations are correct?

Options

A. `1 eV = 9.11 xx 10^(-4) J`
B. `1 L = 1 dm^(3)`
C. `1 J = 1.98 "cal"`
D. 1 atm `= 1.01325` bar

Explanation

To determine which of the given relations are correct, we will analyze each statement one by one.

### Step-by-Step Solution:

1. **First Relation: 1 electron volt = 9.11 × 10^-4 joules**
- The correct value of 1 electron volt (eV) is actually 1.602 × 10^-19 joules.
- Therefore, the statement "1 electron volt = 9.11 × 10^-4 joules" is **false**.

2. **Second Relation: 1 liter = 1 dm³**
- By definition, 1 liter is indeed equal to 1 cubic decimeter (1 dm³).
- This is a standard conversion in metric measurements.
- Therefore, this statement is **true**.

3. **Third Relation: 1 joule = 1.98 kcal**
- The correct conversion is that 1 joule is approximately equal to 0.2388 kilocalories (kcal).
- Therefore, the statement "1 joule = 1.98 kcal" is **false**.

4. **Fourth Relation: 1 atm = 1.01325 bar**
- The standard atmospheric pressure is defined as 1 atm = 1.01325 bar.
- Therefore, this statement is **true**.

### Summary of Correct Relations:
- The correct relations are:
- **Second Relation**: 1 liter = 1 dm³ (True)
- **Fourth Relation**: 1 atm = 1.01325 bar (True)

### Final Answer:
The correct options are **Option B** and **Option D**.