Question

Addition of a solute to pure water causes
A.Negative water potential
B.More negative water potential
C.Positive water potential
D.More positive water potential

Answer 1

Hint: Water potential is defined as the potential energy of water per unit volume when compared to pure water in reference conditions.

Complete answer:
The potential energy of a water per unit volume a solution, when compared to pure water, is known as its water potential. Water potential is considered as the factor which affects the capability of water to move from one place to another osmosis, gravity, capillary action etc. So this factor has been helpful to understand the movements of water in plants through their stem etc. The water will always move from a region of higher water potential to lower water potential and the water will flow until the potential on both sides us balanced. Many factors will result in the change of the value of water potential. For example, if the pressure is increased water potential will also increase. ater potential of pure water is considered to be zero. When a solute is added to a solvent its water potential decrease and in the case of pure water it will become a negative value from zero. Now lest analyse the answers

Option A) Here the water potential of pure water after adding a solute will become negative. Hence this is the correct option
Option B) Here the potential of water is not already negative so it cannot be more negative. Therefore this is an incorrect option
Option C) Upon adding a solute the water potential is decreased, not increased. Therefore it doesn’t become positive. So this is an incorrect option
Option D) Upon adding a solute the water potential is decreased, not further increased. Therefore it doesn’t become positive. So this is an incorrect option

Hence, the correct answer is option (A)

Note: Water potential is measured as potential energy over a unit volume and it is denoted by the Greek letter. It is the sum of different factors that affect it and they are solute or osmosis, reference correction, gravity factor, pressure, humidity and potential due to matrix effects.