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Water’s lower density in its solid form is due to the way hydrogen bonds are oriented as it freezes: the water molecules are pushed farther apart compared to liquid water. With most other liquids, solidification when the temperature drops includes the lowering of kinetic energy between molecules, allowing them to pack even more tightly than in liquid form and giving the solid a greater density than the liquid.

The lower density of ice, illustrated and pictured in [link] , an anomaly, causes it to float at the surface of liquid water, such as in an iceberg or in the ice cubes in a glass of ice water. In lakes and ponds, ice will form on the surface of the water creating an insulating barrier that protects the animals and plant life in the pond from freezing. Without this layer of insulating ice, plants and animals living in the pond would freeze in the solid block of ice and could not survive. The detrimental effect of freezing on living organisms is caused by the expansion of ice relative to liquid water. The ice crystals that form upon freezing rupture the delicate membranes essential for the function of living cells, irreversibly damaging them. Cells can only survive freezing if the water in them is temporarily replaced by another liquid like glycerol.

Ice floes float on ocean water near a mountain range that rises out of the water.
Hydrogen bonding makes ice less dense than liquid water. The (a) lattice structure of ice makes it less dense than the freely flowing molecules of liquid water, enabling it to (b) float on water. (credit a: modification of work by Jane Whitney, image created using Visual Molecular Dynamics (VMD) software W. Humphrey W., A. Dalke, and K. Schulten, “VMD—Visual Molecular Dynamics,” Journal of Molecular Graphics 14 (1996): 33-38. ; credit b: modification of work by Carlos Ponte)

Click here to see a 3-D animation of the structure of an ice lattice. (Image credit: Jane Whitney. Image created using Visual Molecular Dynamics VMD software. W. Humphrey W., A. Dalke, and K. Schulten, “VMD—Visual Molecular Dynamics,” Journal of Molecular Graphics 14 (1996): 33-38. )

Water’s high heat capacity

Water’s high heat capacity is a property caused by hydrogen bonding among water molecules. Water has the highest specific heat capacity    of any liquids. Specific heat is defined as the amount of heat one gram of a substance must absorb or lose to change its temperature by one degree Celsius. For water, this amount is one calorie    . It therefore takes water a long time to heat and long time to cool. In fact, the specific heat capacity of water is about five times more than that of sand. This explains why the land cools faster than the sea. Due to its high heat capacity, water is used by warm blooded animals to more evenly disperse heat in their bodies: it acts in a similar manner to a car’s cooling system, transporting heat from warm places to cool places, causing the body to maintain a more even temperature.

Water’s heat of vaporization

Water also has a high heat of vaporization , the amount of energy required to change one gram of a liquid substance to a gas. A considerable amount of heat energy (586 cal) is required to accomplish this change in water. This process occurs on the surface of water. As liquid water heats up, hydrogen bonding makes it difficult to separate the liquid water molecules from each other, which is required for it to enter its gaseous phase (steam). As a result, water acts as a heat sink or heat reservoir and requires much more heat to boil than does a liquid such as ethanol (grain alcohol), whose hydrogen bonding with other ethanol molecules is weaker than water’s hydrogen bonding. Eventually, as water reaches its boiling point of 100° Celsius (212° Fahrenheit), the heat is able to break the hydrogen bonds between the water molecules, and the kinetic energy (motion) between the water molecules allows them to escape from the liquid as a gas. Even when below its boiling point, water’s individual molecules acquire enough energy from other water molecules such that some surface water molecules can escape and vaporize: this process is known as evaporation    .

Questions & Answers

what is science?
Benedict Reply
Science is the method of acquiring skills and knowledge through experimentation and observation in the World Series
Richmond
where does meiosis occur in male plant reproductive organ
Gimai Reply
plant cell is plasmolysed as a result of the
Favour Reply
of the plant losing water
Esnart
"Head of a pin" means what?
Theresah Reply
types of genotype and types of blood group
Adebusuyi Reply
what is biology
Musa Reply
is the study of cell and structure of an organism
Atem
is the study of characteristics,life processes and phenomana of living organism
Atem
What is Monomer of protein?
Dimpho Reply
What's nutrition and types of nutrition
Jessica Reply
Why is cheetah d fastest animal
Jessica Reply
because they are capable of reaching speeds of up to 70mph
Abu
Thanks
Jessica
what is a cell
Reuben Reply
what is an enzymes
Reuben
a cell is a biological catalyst that speeds up the rate of a chemical reaction without itself been changed
Israel
a cell is smallest unit of life
Francis
an Enzyme helps speed up a chemical reaction
Francis
is the basic structural and functional unit of all organism
Atem
what is deamination
Mutebi Reply
Is the removal of amino radical from amino acid or any other amino compound.
Esnart
what is metabolism
Allen Reply
metabolism is the the combination of all the reaction that occur within your body
xjuicy_editzz
These reaction can be either anabolic (which is the building up of molecules) or can be catabolism (breaking of molecules) but these processes occur simultaneously to maintain homeostasis(internal body environment) within the body.
xjuicy_editzz
hope that helps :D !!
xjuicy_editzz
list 20 element in their order
Dor Reply
hydrogen helium lithium beryllium boron carbon nitrogen oxygen fluorine neon sodium Magnesium aluminium silicon phosphorus sulfur chlorine Aaron potassium calcium -Also if anyone is having trouble remembering the elements I recommend watching "The Periodic Table of elements song" :)
xjuicy_editzz
anabolic, Because ATP is needed
Avuyileji Reply
?
xjuicy_editzz
definition of biology
LENARD Reply
the branch of science that deals with the study of plants and animals
Emmanuel

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Source:  OpenStax, Biology. OpenStax CNX. Feb 29, 2016 Download for free at http://cnx.org/content/col11448/1.10
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