<em>The only difference between a molecule of a compound and a molecule of an element is that in a molecule of an element all the atoms are the same.</em>
<em>Explanation: A molecule of an element all the atoms are the same.</em>
is that in a molecule of an element, all the atoms are the same. For example, in a molecule of water (a compound), there is one oxygen atom and two hydrogen atoms. But in a molecule of oxygen (an element), both of the atoms are oxygen.
Mechanical weathering breaks rocks into smaller pieces without changing their composition. Ice wedging and abrasion are two important processes of mechanical weathering. Chemical weathering breaks down rocks by forming new minerals that are stable at the Earth's surface
