Fluorite can scratch a copper coin but cannot be scratched by a copper coin.
This is because according to Mohs scale of hardness, fluorite has a hardness of four. Copper has a hardness of three. Therefore fluorite is a harder mineral than copper and will scratch copper but it will not be scratched by copper.
Mohs based his scale on the fact that some minerals could scratch others. If one mineral could scratch another but could not be scratched by it, he reasoned that it must be harder.
1. Atrium
2. Ventricle
3.left ventricle
4. they pump blood throughout the body
5.superior vena cava
6. Pulmonary vein
7.Four heart valves control the flow of blood through the heart. They act as one-way doors, opening to let blood exit or enter a chamber, then closing to keep blood from flowing backward.
When blood glucose levels decrease, Your liver which is a glycogen storage converts glycogen to glucose and releases it into circulation. Further energy ( ATP Molecules ) is obtained by the TCA Cycle with subtraces like Fat and Protein.
