Surface Tension

Q. The osmotic pressure of a solution of $NaClis0.10atm$ and that of a glucose solution is $0.20atm$. The osmotic pressure of a solution formed by mixing $1L$ of the sodium chloride solution with $2L$ of the glucose solution is $x\times {10}^{-3}atm.x$ is __________. (nearest integer)

Q. When the temperature of a liquid increases, its surface tension
.

1. increases
2. decreases
3. remains constant

Q. At same temperature, hydrogen is more soluble in water than helium. Which of them has higher value of K_H and why?

Q. Which of the following is colligative property?

1. Osmotic pressure
2. Boiling point elevation
3. Electrical conductivity
4. Vapour pressure

Q. When the temperature increases, the surface tension of water

1. increases
2. remains constant
3. decreases

Q. How does the surface tension of a liquid vary with increase in temperature?

1. Remains the same
2. Increases
3. Decreases
4. No regular pattern

Q.

The surface tension of which of the following liquid is maximum:

1. ${\mathrm{C}}_2{\mathrm{H}}_5\mathrm{OH}$

2. ${\mathrm{CH}}_3\mathrm{OH}$

3. ${\mathrm{H}}_2\mathrm{O}$

4. ${\mathrm{C}}_6{\mathrm{H}}_{6_{}}$

Q. Why does water rise in a capillary tube?

Q.

Define vapour pressure?

Q.

Why does temperature decrease with pressure?

Q.

Why is no force required to move an object which is in motion with a constant velocity?

Q.

The pressure and temperature determine the state of a substance. Explain

Q.

The shape of drops and bubbles are spherical due to its

1. Thrust on drop

2. Surface tension

3. Viscosity

4. Residual pressure

Q.

Which of the following property of water can be used to explain the spherical shape of rain droplets?

(a) Viscosity (b) Surface tension

(c) Critical phenomena (d) Pressure

Q. A soap bubble is blown slowly at the end of a tube by a pump supplying air at a constant rate. Draw a graph to represent the variation between the excess pressure inside the bubble with time.

Q. at 100^° C the vapour pressure of a solution of 6.25 g of a solute in 100g waterb is 732 mm . if kb =052, th bil boling point of solution?

Q.

Why does sharp glass edge become smooth on heating it upto its melting point in a flame? Eplain which property of liquids is responsible for this phenomenon.

Q.

When an impurity is added to a liquid, its surface tension

Q.

How do mosquitoes stand on water?

Q.

The meniscus of water is ________.

1. Convex

2. Plane

3. Concave

4. Uncertain

Q.

Explain why alkyl halides though polar are immiscible with water?

Q. There is a depression in the surface of the liquid in a capillary when

1. The cohesive force is greater than the adhesive force.
2. The cohesive force is smaller than the adhesive force.
3. The cohesive and adhesive forces are equal.
4. None of the above is true.

Q. why absorption is not a surface phenomenon

Q.

How does the surface tension of a liquid vary with an increase in temperature?

(a) Remains same (b) Decreases

(c) Increases (d) No regular pattern is followed

Q. At the same temperature and pressure, which of the following gas will be adsorbed in more proportion?
(A) Cl_{​​​​​2}
(B) N_{​​​​​​2}
(C) H_{​​​​​​2}
(D) NH_​​​3
Ans: (D)
Why does NH_{​​​​​3} get adsorbed more amongst the following?

Q. Read the passage given below and answer the following questions:
Read the passage given below and answer the following questions:
A soluble solid in solution has the effect of raising its boiling point and depressing its freezing point. The addition of non-volatile substances to a solvent decreases the vapor pressure and the added solute particles affects the formation of pure solvent crystals. According to many researches the decrease in freezing point directly correlated to the concentration of solutes dissolved in the solvent. This phenomenon is expressed as freezing point depression and it is useful for several applications such as freeze concentration of liquid food and to find the molar mass of an unknown solute in the solution. Freeze concentration is a high quality liquid food concentration method where water is removed by forming ice crystals. This is done by cooling the liquid food below the freezing point of the solution. The freezing point depression is referred as a colligative property and it is proportional to the molar concentration of the solution (m), along with vapor pressure lowering, boiling point elevation, and osmotic pressure. These are physical characteristics of solutions that depend only on the identity of the solvent and the concentration of the solute. The characters are not depending on the solute's identity.

Identify which of the following is colligative property:

1. Freezing point
2. Boiling point
3. Osmotic pressure
4. All of the above

Q.

More the intermolecular force of attraction, __________________will be the intermolecular space between the molecules.

Q. There is a depression in the surface of the liquid in a capillary when

1. The cohesive force is smaller than the adhesive force.
2. The cohesive force is greater than the adhesive force.
3. The cohesive and adhesive forces are equal.
4. None of the above is true.

Q.

Name two phenomena that can be explained on the basis of surface tension.

Q.

In the following question a statement of Assertion (A) followed by a statement of Reason (R) is given. Choose the correct option out of the choices given below in each question.

Assertion (A) Liquids tend to have the maximum number of molecules at their surface.

Reason (R) Small liquid drops have spherical shape.

(a) Both A and R are true and R is the correct explanation of A

(b) Both A and R are true but R is the correct explanation of A

(c) A is true but R is false

(d) A is false but R is true