revison notes biological ompound inorganic ions and water answers

1.     Water is essential as a medium for metabolic reactions; it is a constituent of cells and many key elements are found dissolved in aqueous solution; water also provides a habitat for aquatic organisms.

2.     tabel on weebly

3.     Macronutrients: needed in small amounts (e.g. magnesium is a constituent of the chlorophyll pigment in leaves; iron is a constituent of haemoglobin in blood; phosphate is found in plasma membranes as the polar part of phospholipids, as well as in nucleic acids and ATP; calcium is a constituent of bones and teeth).Micronutrients: needed in minute (trace) amounts, e.g. copper, zinc

4.     tabel...

5.     dipole

6.     water is a polar molecule and has no overall charge. The oxygen end of the molecule has a partial  negative charge and the hydrogen end of the molecule has a partial  positive charge. This is called a dipole. 

7.     The small partial charges occur because the oxygen atom is electronegative and draws the electrons (making the covalent bond with hydrogen) closer towards itself. So the partial charges are only very small and are not full charges such as + and -.

8.     When two water molecules are in close contact their opposing partial charges attract each other, forming a hydrogen bond. hydrogen bonds are weak but because of the very large number of them in water they stick together in a strong lattice framework. This sticking  together of water molecules is called cohesion.

9.     This means that tall columns of water can be drawn up xylem vessels inside tall trees.   

10.   strong lattice framework

11.    look on weebly. 

12.   Water has strong cohesive forces (stick together) because there are many Hydrogen bonds which are collectively strong

13.    At ordinary temperatures water has the highest surface tension …