Phosphate in soil

Question

a) precipitates at low pH
b) precipitates at high pH
c) precipitates at low and high pH
d) does not precipitate at any pH
e) all of the above
f) none of the above
28. Potassium in plants:
a) causes the green color
b) is responsible for root elongation
c) regulates osmotic potential in cells
d) all of the above
e) none of the abov

Answer 1

For your questions:

1. Phosphate in soil:

   • The correct answer is c) precipitates at low and high pH. Phosphate can form insoluble compounds in both highly acidic (low pH) and highly alkaline (high pH) soils. In low pH, it often forms insoluble iron and aluminum phosphates, while at high pH, it may precipitate as calcium phosphate.

2. Potassium in plants:

   • The correct answer is c) regulates osmotic potential in cells. While potassium does play a role in plant growth and development, particularly in processes such as regulating stomatal opening (which helps maintain osmotic balance), it is most noted for its role in osmotic potential. It is not specifically responsible for root elongation or the green color of plants (which is primarily due to chlorophyll, often associated with nitrogen).

So for Potassium, the closest correct answer is e) none of the above, if you are considering that none of the options truly encompass what potassium does comprehensively.