To solve the question regarding the correct statements about cesium chloride and defects in crystals, we will analyze each statement step by step.
### Step 1: Analyze the first statement
**Statement:** Cesium chloride crystals likely show Schottky defect.
**Explanation:**
- Schottky defect occurs when an equal number of cations and anions leave the crystal lattice, creating vacancies.
- For Schottky defect to occur, the sizes of cations and anions should be similar.
- In cesium chloride (CsCl), the size of cesium cation (Cs⁺) and chloride anion (Cl⁻) are indeed similar.
- Therefore, this statement is **correct**.
### Step 2: Analyze the second statement
**Statement:** Cesium chloride cannot show Frenkel defect.
**Explanation:**
- Frenkel defect occurs when a cation leaves its normal position and occupies an interstitial site, which typically requires a significant size difference between the cation and anion.
- In CsCl, the size difference between Cs⁺ and Cl⁻ is not large enough to facilitate a Frenkel defect.
- Therefore, this statement is **correct**.
### Step 3: Analyze the third statement
**Statement:** The photosensitivity of AgBr is due to the presence of Frenkel defect in it.
**Explanation:**
- AgBr (silver bromide) does exhibit Frenkel defects, which contribute to its photosensitivity.
- This is because the Frenkel defect allows for the movement of Ag⁺ ions, which is crucial in the photographic process.
- Therefore, this statement is **correct**.
### Step 4: Analyze the fourth statement
**Statement:** Crystals having F-centers are colored and paramagnetic.
**Explanation:**
- F-centers are created when an anion vacancy is filled by an unpaired electron, leading to color in the crystal.
- For example, NaCl can appear yellow due to F-centers, and these centers can contribute to paramagnetism because of the presence of unpaired electrons.
- Therefore, this statement is **correct**.
### Conclusion
After analyzing all the statements, we find that:
- **Correct Statements:** A (Cesium chloride shows Schottky defect), B (Cesium chloride cannot show Frenkel defect), C (Photosensitivity of AgBr is due to Frenkel defect), D (Crystals with F-centers are colored and paramagnetic).
Thus, the correct answer is **A, B, C, and D**.
