BioChem 2.2 Water Flashcards
Draw and label a diagram of a water molecule
Water is made out of the covalent bondings of two positive hydrogen atoms and one negative oxygen atom.
What is a hydrogen bond?
It is the bond between different water molecules. This is due to the fact that the water molecule has polar charged regions that attract itself to other water molecules’ polar regions.
What is a thermal property of water?
Thermal properties of water include heat capacity, boiling and freezing point.
Does water have a low or high heat capacity?
Water has a high heat capacity meaning that it takes much more energy to increase change its temperature than, say methane.
Why does water have a high heat capacity?
Water has a high heat capacity due to its strong hydrogen bonds that make it difficult for them to break without sufficient energy. This means that water remains relatively stable.
This property is often used for animals as they can cool themselves or warm themselves in the water.
Water takes boils at a higher temperature than methane. Why is this?
Due to water’s high latent heat capacity, it takes water molecules much more energy to convert from liquid to gas. This means that because of the strong hydrogen bonds, they require a lot of energy to break apart in order for water to evaporate.
Why is sweating ineffective in a very humid climate?
Sweat is released in order cool the body down, as the sweat evaporate, leaving the surface of the skin cooler as all the high energy (hot) molecules are released into the atmosphere.
In a humid climate, the air already contains lots of water which means that there is not enough space for the sweat to evaporate, leaving the body hot and drenched.
Why is the high boiling point of water vital to life?
The high boiling point enables organisms to survive in hotter climates. If water did not have such high specific heat capacity, organisms would boil along the water and be unable to survive.
How does water in its solid state become beneficial to organisms?
When water freezes, it becomes less dense. This means that the ice blocks will float atop of the water. Ice covered surface on lakes and seas acts as an insulator for the water underneath to maintain habitats for organisms.
How do plants benefit from water properties?
One of the properties water has is its cohesion. Due to the hydrogen bonds, water is able to be transported from the roots to leaves through long columns.
What property is present when sugar is mixed with water?
When sugar is mixed into water, it dissolves presenting water’s solvent properties because of its polarity.
How is oxygen transported in blood?
Oxygen has low solubility in water and therefore needs to be transported through haemoglobins.
Which molecules have high solubility in water and can be transported through blood plasma?
Glucose, amino acids and sodium chloride are soluble.
If molecules have low solubility in water, how can they be transported in blood?
Molecules like fats and cholesterol have low solubility, and need to be transported inside lipoproteins in blood.
