Each water molecule has 10 protons and 10 electrons, for a net charge of 0. The shape of each water molecule influences the way it interacts with other water molecules and with other substances. Water acts as a polar solvent because it can be attracted to either the positive or negative electrical charge on a solute. The slight negative charge near the oxygen atom attracts nearby hydrogen atoms from water or positive-charged regions of other molecules.
The slightly positive hydrogen side of each water molecule attracts other oxygen atoms and negatively-charged regions of other molecules. The hydrogen bond between the hydrogen of one water molecule and oxygen of another holds water together and gives it interesting properties, yet hydrogen bonds are not as strong as covalent bonds. This interaction is called hydration or dissolving.
Actively scan device characteristics for identification. Use precise geolocation data. Select personalised content. Create a personalised content profile. Measure ad performance. Select basic ads. Create a personalised ads profile. Select personalised ads. The chemical composition of water is H 2 O — two hydrogen atoms and one oxygen atom. The properties of water are special because of the way its atoms bond together to form a water molecule, and the way the molecules interact with each other.
When the two hydrogen atoms bond with the oxygen , they attach to the top of the molecule rather like Mickey Mouse ears. This molecular structure gives the water molecule polarity , or a lopsided electrical charge that attracts other atoms. The end of the molecule with the two hydrogen atoms is positively charged. The other end, with the oxygen, is negatively charged.
What does this mean for us? When a polar substance is put in water, the positive ends of its molecules are attracted to the negative ends of the water molecules, and vice versa. The attractions cause the molecules of the new substance to be mixed uniformly with the water molecules. Water dissolves more substances than any other liquid — even the strongest acid! Wherever water goes, it carries dissolved chemicals, minerals, and nutrients that are used to support living things.
Because of their polarity, water molecules are strongly attracted to one another, which gives water a high surface tension. Without liquid water, there could be no life as we know it.
Life is possible on Earth because it exists in the so-called Goldilocks Zone , where it's neither too hot, nor too cold, but just right for liquid water to exist. In our solar system, the only other places where liquid water may exist in large volumes is under the ice of the moons of Jupiter and Saturn, where hydrothermal vents may allow chemosynthesis to occur. The origin of Earth's water is not completely understood, but much of the water is likely to have come from extra-terrestrial sources.
Ice caps exist at both poles because they receive less solar radiation than equatorial regions, and the ice caps have a significant effect on both climate and sea level. There is growing evidence that the ice caps are shrinking as a result of human caused global climate change. The long-sought Northwest Passage has become navigable for at least part of the year for the first time in recorded history.
Tides : Gravitational interaction between the Earth's water and the Moon results in daily high and low tides. Tidal extremes were much greater in the Earth's early history, when the Moon was half as distant as it is now, and there is speculation that tides may have initiated or at least accelerated the evolution of life on Earth.
Water molecules attract each other due to polarity. Polarity : Although the net charge of a water molecule is zero, water is polar because of its shape. The hydrogen ends of the molecule are positive and the oxygen end is negative. Each hydrogen atom is covalently bonded to the oxygen via a shared pair of electrons. Oxygen also has two unshared pairs of electrons.
Thus there are 4 pairs of electrons surrounding the oxygen atom, two pairs involved in covalent bonds with hydrogen, and two unshared pairs on the opposite side of the oxygen atom. Oxygen is an "electronegative" or electron "loving" atom compared with hydrogen.
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