Water Flashcards
water
What are the two kinds of bonds between particles?
2
- Ionic
- Covalent
water
What is ionic bonding?
single answer
The attraction between positive and negative ions
water
What is covalent bonding?
single answer
The attraction between the nuclei of an atom and the electrons they share
water
Water molecules are [ ] and [ ] form between them
2
- Polar
- Hydrogen bonds
water
Are the electrons in the covalent bonds between hydrogen and oxygen shared equally or unequally? Why?
In the water molecule
2
- Unequally
- Because the electrons have a greater attraction to the larger, positive, nucleus of the oxygen atom
water
The water molecules are said to have a []
clue: 2, north []
single answer
Dipole
What is a dipole?
1
A separation of charge
positive at one pole, negative at the other
water
What is a hydrogen bond?
single answer
A bond between water molecules
water
Why do hydrogen bonds form?
single answer
Because the partially positive hydrogen atoms on one molecule are attracted to the partially negative oxygen atoms of another
water molecule can bond with up to four others
water
What is cohesion?
definition and explanation
2
- Definition: The tendency of molecules of the same substance to stick together
- Explanation: Hydrogen bonding between water molecules cause them to stick together
water
What is adhesion?
definition and explanation
2
- Definition: The tendency of molecules to stick to surfaces or other molecules
- Explanation: Most surfaces are polar/charged, so the partially charged water molecules will be attracted to the surface
water
What is surface tension?
definition + 3-step explanation
4
The formation of a dense layer on the surface layer of water due to
1. Attraction of water molecules within body of water to other water molecules in all directions
2. Attraction of water molecules at surface to the side and below them
3. The downwards net attraction
water
What is capillary action?
definition and 2-step explanation
3
Movement of water through tiny tubes called xylem
1. Water is attracted to the surface of a space through adhesion
2. Other water molecules follow through cohesion
water: thermal properties
What is the heat of vaporization? How does it apply to water?
what must happen for water to vaporise?
single answer
- The energy required to change a liquid to a gas
- To become a gas, hydrogen bonds between water molecules must be broken. Breaking bonds requires energy.
water: thermal properties
What is specific heat capacity?
single answer
The energy required to raise 1g of a substances by 1C
degree celcius
water: thermal properties
Is the specific heat capacity/heat of vaporization of water high or low?
single answer
Water’s heat capacity and heat of vaporization is high
water: thermal properties
What are the applications of the thermal properties of water?
2
- Cooling
- Maintaining ideal temperatures for metabolic rxns
water: thermal properties
Explain how water’s application of cooling works
explain process
2
- The body uses energy to evaporate water from the surface of the body
- When water evaporates, it cools the body’s skin
Animals can cool themselves by sweating or panting
water: thermal properties
Explain how water’s application of maintaining ideal temperatures for metabolic rxns works
explain why water is ideal for this and two applications
3
- Water has a high specific heat capacity, meaning it does not change temperatures quickly
- Since the body is 60-75% water, the body avoids reaching extreme temperatures, remaining ideal for metabolic rxns (around 37C)
- Large bodies of water maintain a relatively stable thermal environment for aquatic organisms
water: solvent properties
Why can water dissolve well in a wide range of biologically important substances?
explain why water is ideal and how it dissolves substances
2
- Most biologically important substances are polar/charged so the polar water molecules are attracted to them
- Water molecules surround the substance particles, allowing them to dissolve
water: solvent properties
Explain the application of the solvent properties of water to bodily transport
example: blood
single answer
The dissolved nutrients and other substances are transported throughout the body by blood
water: solvent properties
Explain the application of the solvent properties of water to bodily metabolism
- Many rxns require substances to be dissolved
- The watery environments of the cytoplasm, stroma, chloroplast, and matrix of the mitochondria (+) dissolve the substances, allowing the rxns to take place
water
Substances can be [] or []
in regards to their relationship with water
2
- Hydrophilic
- Hydrophobic
water
Hydrophilic substances can be…
regarding polarity (define, though not important)
2
- Polar: with functional groups like (-OH) that have polar bonds
- Charged: Many contain the functional group (-COOH) which partially ionizes the in water and creates (-COO-+H+)
Hydrophobic substances are…
regarding polarity (define)
single answer
Nonpolar: often with regions containing only carbon and hydrogen
i.e. methane or fatty acid tails of phospholipids
water: transport and solubility
Glucose
solubility and mode of transport
- High solubility
- Dissolves in the blood plasma
water: transport and solubility
Amino acids
solubility and mode of transport
2
- high solubility
- dissolves in blood plasma
water: transport and solubility
Cholesterol
solubility and mode of transport
2
- low solubility
- they are carried by lipoprotein complexes with hydrophilic amino acids on the outside and a binding region for cholesterol with hydrophobic amino acids
water: transport and solubility
Fats
solubility and mode of transport
2
- low solubility
- carried by plasma proteins with hydrophilic amino acids on the outside and a binding region for fats with hydrophobic amino acids
water: transport and solubility
Oxygen
solubility and mode of transport
2
- low solubility
- carried by hemoglobin in red blood cells
water: transport and solubility
Sodium Chloride
solubility and mode of transport
2
- high solubility
- dissolves easily in the blood plasma
