Eka-aluminium forms chloride of the type :

Explanation

To solve the question regarding the type of chloride formed by Eka-aluminium, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Eka-aluminium**:
- Eka-aluminium is a term coined by Mendeleev for an element that was predicted to have properties similar to aluminium. It is now known as Gallium (Ga).

2. **Identifying the Similarities**:
- Mendeleev proposed that Eka-aluminium would exhibit similar chemical properties to Gallium.

3. **Analyzing Chloride Formation**:
- Gallium (Ga) forms a chloride of the type GaCl3. This indicates that it has a +3 oxidation state when forming chlorides.

4. **Inferring the Chloride Type for Eka-aluminium**:
- Since Eka-aluminium is predicted to have similar properties to Gallium, we can deduce that it would also form a chloride of the same type.

5. **Conclusion**:
- Therefore, Eka-aluminium will form a chloride of the type ECl3, where E represents Eka-aluminium.

### Final Answer:
Eka-aluminium forms chloride of the type ECl3.