<em>Water has unique chemical characteristics in all three states—solid, liquid, and gas—thanks to the ability of its molecules to hydrogen bond with one another. Since living things, from human beings to bacteria, have a high water content, understanding the unique chemical features of water in its three states is key to biology.
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<em>In liquid water, hydrogen bonds are constantly being formed and broken as the water molecules slide past each other. The breaking of these bonds is caused by the energy of motion (kinetic energy) of the water molecules due to the heat contained in the system.
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<em>When the heat is raised (for instance, as water is boiled), the higher kinetic energy of the water molecules causes the hydrogen bonds to break completely and allows water molecules to escape into the air as gas. We observe this gas as water vapor or steam.
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<em>On the other hand, when the temperature drops and water freezes, water molecules form a crystal structure maintained by hydrogen bonding (as there is too little heat energy left to break the hydrogen bonds). This structure makes ice less dense than liquid water.</em>
The following contains stem cells that can produce only their own type of cells is the answer B adult
<span>The atomic number of a neutral atom is equal to
the number of protons and the number of electrons of the atom. The atomic
weight meanwhile is equal to the sum of the number of protons and number of
neutrons. We add therefore the number of protons and number of neutrons </span>
