Cohesion
Trending Questions
Q. B2 is more stable than F2 then also bond length of B2 is greater than F2. Why?
Q. Which of the following is the most acceptable theory for movement of water through plants?
- Cohesion tension theory
- Passive transport
- Root pressure theory
- Munch’s hypothesis
Q.
Explain the relationship between absorption of water and transpiration.
Q. Molecules of water are held together by hydrogen bonds.This mutual intermolecular attractive force is called _______.
- capillarity
- imbibition
- cohesive force
- adhesive force
Q. How does resonance affect bond length? Direct variation or indirect variation?
Q. Cohesion is the mutual attraction between water molecules.
- False
- True
Q.
Name the following:
Binding of water molecules to each other.
Q.
Define: Cohesive force
Q. Transpiration cohesion theory explains that, the upward pull of water is transmitted from top to bottom by cohesion of molecules caused by
- Hydrophilic cell walls
- Hydrogen bonds
- Oxygen bonds
- Surface tension
Q. Who had proposed theory of cohesion and adhesion forces?
- Dixon and Benson (1885)
- Dixon and Jolly (1950)
- Sir Jagdish Chandra Bose (1850)
- Dixon and Jolly (1894)
Q. Cohesion-tension theory is related to
- Transpiration
- Photosynthesis
- Respiration
- Ascent of sap
Q. The rupture and fractionation do not usually occur in the water column in vessels/tracheids during the ascent of sap because of
- Lignified thick walls
- Cohesion and adhesion
- Weak gravitational pull
- Transpirational pull
Q. Give an experiment to demonstrate cohesion - tension theory.
Q.
Cohesion and adhesion theory is otherwise called
Root pressure theory
Pulsation theory
Relay pump theory
Transpiration pull theory
Q.
Give biological reason for the following:
Sticking of water to xylem walls.
Q. Cohesion-tension theory regading ascent of sap was given by
- Dixon and Jolly
- J.C. Bose
- Christian Wolf
- Godlewski
Q.
What is transpiration pull?
Q. Water supply in the plant is due to
- Osmosis
- Guttation
- Cohesion force
- Imbibition
Q. Which one of the following theories for ascent of sap was proposed by eminent Indian Scientist J.C.Bose
- Pulsation theory
- Transpiration Pull theory
- Root pressure theory
- Atmospheric pressure theory
Q.
In a chemistry lab, Rina took some mercury and water in two test tubes separately. Then she drained off both the liquids and on observing the empty test tubes, found some differences. Can you guess what the difference is? Explain with appropriate reasons
Q. Assertion :The water molecules are held together from root cells to the vascular bundle because of cohesive force. Reason: Water does not ascend in the plant because of transpiration pull.
- Both Assertion and Reason are correct and Reason is the correct explanation for Assertion.
- Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion.
- Assertion is correct but Reason is incorrect.
- Assertion is incorrect but Reason is correct.
Q. Where does transpiration cohesion pull theory works?
- Active absorption
- Inactive absorption
- Active and Inactive absorption
- None of these
Q. Backbonding and its effects on bond energy, bond length, etc.
Q. The force with which water molecules are held together in xylem is
- Imbibition pressure
- Osmotic pressure
- Adhesion force
- Cohesion force
Q. The most important force which pulls the water in trees in
- Cohesive force
- Electromagnetic force
- Imbibition force
- Osmotic force
Q. Force responsible for the ascent of sap is:
- Capillary force
- Root pressure
- Transpirational pull
- All the three
Q. Force of cohesion develops due to
- Attraction between similar molecules.
- Attraction between different molecules.
- Surface tension at the interface.
- All the above.
Q.
Name the following:
iii) Force between water molecules.
