1) A mountain is created by faulting while hill is created by either faulting or erosion.
The faulting, that happens because the rocks underneath the Earth’s surface are constantly moving and changing the landscape. Hills formed by faulting can eventually become mountains.
A natural mound of earth created either by faulting or erosion is a hill.
A natural mound of earth created by faulting is mountain.
2) A mountain is often named whereas hill is often unnamed.
Mountains form a major landform on the earth. They cover the maximum area and their ranges are wide spread across the country. Hence mountains are named. Hills do not form major landform as compared to mountains so they are not named.
3) The altitude and elevation of the hill is low while the altitude and elevation of the mountain is high.
Hills are usually formed by either by faulting or erosion hence the altitude and elevation is less. Mountains are a natural mound of earth created by faulting. Hence mountains have high altitude and elevation.