Consider the following stetements in reference to the structure of atom
1. Isopes are the atoms of the same element having same atomic number but different mass - numbers .
2. Isobars are the atoms of different elements having different atomic number of different atomic number but same mass - number .
Which of above statement is/are correct ?

Options

A. Only 1
B. Only 2
C. 2 and 3
D. All of these

Answer

To determine which statements about isotopes and isobars are correct, let’s analyze each statement step by step.

### Step 1: Understand the definition of isotopes.
- **Isotopes** are atoms of the same element that have the same atomic number but different mass numbers. This means they have the same number of protons but a different number of neutrons. For example, hydrogen has three isotopes: protium (1 proton, 0 neutrons), deuterium (1 proton, 1 neutron), and tritium (1 proton, 2 neutrons).

### Step 2: Evaluate the first statement.
- The first statement claims: "Isotopes are the atoms of the same element having the same atomic number but different mass numbers."
- This statement is **correct** because it accurately describes isotopes.

### Step 3: Understand the definition of isobars.
- **Isobars** are atoms of different elements that have different atomic numbers but the same mass number. This means they have a different number of protons but the same total number of protons and neutrons. For example, carbon-14 and nitrogen-14 are isobars because they both have a mass number of 14 but different atomic numbers (6 for carbon and 7 for nitrogen).

### Step 4: Evaluate the second statement.
- The second statement claims: "Isobars are the atoms of different elements having different atomic numbers but the same mass number."
- This statement is also **correct** as it accurately describes isobars.

### Conclusion:
Both statements are correct. Therefore, the answer to the question is that both statements are true.

### Final Answer:
Both statements are correct.