Water Flashcards
What is the structure of water?
1 oxygen atom joined to 2 hydrogen atoms held by covalent bonds
Why is water a dipolar molecule?
The shared electrons are pulled towards the more electronegative oxygen atom so it gains a slightly negative charge, leaving the hydrogen atoms with slightly positive charges.
What bonds can water molecules form when they interact?
Hydrogen bonds
How is water a solvent?
Water is polar, the slightly negative oxygens are attracted to the positive ions of an ionic compound and the slightly positive hydrogens are attracted to the negative ions. The ions are surrounded by water molecules and the compound dissolves.
Why is water being the universal solvent useful?
- Most biological reactions take place in solution e.g the cytoplasm.
- Dissolved substances can be transported around the body e.g ions can be transported in the blood plasma.
Why does water have a high specific heat capacity?
A lot of energy is needed to raise the temperature of 1g of water by 1 degree celcius. The hydrogen bonds can absorb a lot of energy before being broken so a lot of energy is needed to break the hydrogen bonds and heat the water.
Why is it useful that water has a high specific heat capacity?
Water is resistant to rapid changes in temperature. A lot of organisms are made up of water which allows the maintenance of internal body temperature.
