In which case does the thermal conductivity increase from left to right

Options

A. Al, Cu, Ag
B. Ag, Cu, Al
C. Cu, Ag, Al
D. Al, Ag, Cu

Answer

To determine in which case the thermal conductivity increases from left to right, we need to analyze the thermal conductivity of different materials based on their properties. Here's a step-by-step solution:

### Step 1: Understand Thermal Conductivity
Thermal conductivity is a measure of a material's ability to conduct heat. Materials can be classified as conductors (like metals) or insulators (like wood or rubber) based on their thermal conductivity.

**Hint:** Remember that conductors have free electrons that facilitate heat transfer, while insulators have bound electrons that do not allow heat transfer effectively.

### Step 2: Identify the Types of Conduction
There are two main types of conduction:
1. **Lattice Conduction**: This occurs in insulators where heat is transferred through the vibration of atoms.
2. **Electronic Conduction**: This occurs in metals where free electrons move and transfer heat.

**Hint:** Focus on how the presence of free electrons in metals enhances thermal conductivity compared to insulators.

### Step 3: Compare Materials
Common materials to compare for thermal conductivity include:
- **Insulators**: Wood, rubber, glass
- **Conductors**: Silver (Ag), Copper (Cu), Aluminum (Al)

**Hint:** Recall that metals like silver and copper are known for their high thermal conductivity due to their free electrons.

### Step 4: Order the Materials by Thermal Conductivity
Based on known values of thermal conductivity:
- Silver (Ag) has the highest thermal conductivity.
- Copper (Cu) follows.
- Aluminum (Al) is next.
- Insulators like wood or rubber have significantly lower thermal conductivity.

**Hint:** Use the common knowledge that silver is the best conductor, followed by copper and aluminum.

### Step 5: Conclusion
From left to right, the order of thermal conductivity increases as follows:
- Insulators (low thermal conductivity) → Aluminum → Copper → Silver (high thermal conductivity)

Thus, the correct option indicating the increasing order of thermal conductivity from left to right is:
- **Silver (Ag) > Copper (Cu) > Aluminum (Al)**

**Final Answer:** The order of increasing thermal conductivity from left to right is: Insulators < Aluminum < Copper < Silver.