A spontaneous process is an ...... process and occurs in ...... direction only.

Explanation

To answer the question, "A spontaneous process is an ...... process and occurs in ...... direction only," we can break it down into two parts.

### Step-by-Step Solution:

1. **Understanding Spontaneous Processes**:
- A spontaneous process is defined as a process that occurs naturally without needing to be driven by an external force.

2. **Identifying the Type of Process**:
...