The natural flow of rivers can be affected by several factors, such as building dams to provide drinking water, pumping of groundwater, climate change, and building of lands that change how natural water runs into surfaces and into rivers. All of these also disrupt the balance of ecosystem in the area.
They are on the periodic table
The chemical formula for water is H2O which means that every molecule of water has 2 atoms of hydrogen (H) and one atom of oxygen (O). Here comes the key part. From the Periodic Table of Elements, one sees that one molecule of oxygen atoms weigh 16 grams.
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