SPEC POINT 1.2

Question 1

What properties does water have that make it cohesive and a solvent?

Answer 1

Water has unevenly shared electrons in a covalent bond, creating a dipole - this means that hydrogen bonds can form between the negative and positive dipoles of water molecules

Question 2

What is cohesion and adhesion and why is it important that water has these 2 properties in transport?

Answer 2

Cohesion - attraction of water molecules to each other
Adhesion - attraction of water molecules to other molecules
This means that water flows easily

Question 3

Explain why water is a good transport medium:

Answer 3

1. Water is composed of two hydrogen atoms covalently bonded to oxygen. Each O-H bond has a dipole, which makes the water molecule overall, polar, with a partially negative oxygen and partially positive hydrogens
2. Water molecules have hydrogen bond between them so they are cohesive and result in water being a liquid that can transport substances according to pressure gradients
3. They are excellent solvents and can interact with opposite charges on other molecules to dissolve them for efficient transport (glucose, oxygen, mineral ions, amino acids, carbon dioxide, urea, soluble proteins)
4. Water is a liquid so it has the ability to flow