"Tranquil" vs. "serene": a quiet comparison

What is similar?
Both "tranquil" and "serene" describe a state of calmness and peacefulness. They are often used to depict environments or atmospheres that are quiet and free from disturbance.
What is different?
"Tranquil" emphasizes the absence of noise or agitation and is frequently used to describe physical settings. "Serene" conveys a deeper sense of inner peace and untroubledness and can describe both environments and personal dispositions.
Which one is more common?

Examples of usage
Tranquil- The tranquil lake reflected the clear blue sky.
- She enjoyed the tranquil atmosphere of the countryside.
- After the storm, the sea became tranquil again.
- He had a serene expression on his face despite the chaos around him.
- The serene beauty of the mountains captivated her.
- Meditation helped her maintain a serene state of mind.