Please answer. QUESTION4 You\'ve seen density in action before, but you\'ve prob
ID: 1884027 • Letter: P
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Please answer.
QUESTION4 You've seen density in action before, but you've probably never realized it. Does wood sink in water? No, it floats (until it is water-logged, at least). What else floats in water? A duck! Both float due to their densities being less than that of water. Do very small rocks float in water? No, because they have a higher density than water. These are examples of density in action. There isn't a magic density value, such as 1g/cm3, that causes objects to "float". In order for an object to float, its density must simply be less than that of the materials surrounding it. One common way to decrease an object's density is to heat up the object. Think of a hot air balloon. The reason for this is that objects expand (increase in volume) when heated and contract (decrease in volume) when cooled. With this in mind, why do icebergs float in oceans? a-Water has the unusual property of also increasing in volume when frozen, which lowers its density. o b. Icebergs are composed of frozen fresh water, not saltwater, that break away from glaciers. o c. Oceans have higher salinity, and thus greater density than icebergs d. All of these answers are correct.Explanation / Answer
Option a) is correct
Density = Mass / Volume
When water cools to form ice(solid phase ), the hydrogen bonding in water form a lattice structure which creates more space between water molecules than in water (liquid phase)
Therefore for the same mass(weight) of water, volume of ice is less than water.
that means density if ice is less than water and a object FLOATS if its density is less than water
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Option b) is correct
Icebergs are composed of fresh water,not salt water,that break away from glaciers.The statement is correct.
In cold regions where it snows all the time,new layer of snow is added on top which compresses bottom layers and this compression forces snow to recrytalize and forms glaciers. Snow is caused by precipitation (precipitation is fresh water obtained from evaporation and condensation) and not by freezing salt water.
(Note: when we add salt (a impurity) to water its freezing point decreases . that means it is possible to make ice cubes from salt water but the temperature should be far less than 0 deg Celsius which is the freezing point of pure water)
Option c) is correct
When we disolve salt in water the volume does not increases . salt take up the molecular spaces of water molecules.Therefore density increases.
Icebergs are made of frozen freshwater, so less denser than sea water which has high salinity
So objects with less density floats on liquid with high density
Option d ) is the ANSWER
Since all the above options are correct