Give the correct order of initials T(true) or F(false) for following statements.
(a) Micelles formation takes place only above craft temperature
(b)ZSM-5 is a type of zeolites used as a catalyst in petrochemical industries.
(c)A micell is an aggregation of surfactants in in aqueous solution, often spherical
(d) Lyophilic sols are irreversible sols

Options

A. T F F T
B. T T F F
C. T T T F
D. F T T F

Answer

To solve the question, we need to evaluate each statement and determine whether it is true (T) or false (F). Let's analyze each statement step by step:

### Step 1: Analyze Statement (a)
**Statement:** Micelles formation takes place only above craft temperature.
**Evaluation:** This statement is true. Micelles form when surfactants are present above a certain temperature known as the Kraft temperature (Tf) and above a specific concentration known as the critical micelle concentration (CMC).
**Conclusion:** T

### Step 2: Analyze Statement (b)
**Statement:** ZSM-5 is a type of zeolites used as a catalyst in petrochemical industries.
**Evaluation:** This statement is also true. ZSM-5 is indeed a type of zeolite that is widely used as a catalyst in various petrochemical processes, including cracking and isomerization.
**Conclusion:** T

### Step 3: Analyze Statement (c)
**Statement:** A micelle is an aggregation of surfactants in aqueous solution, often spherical.
**Evaluation:** This statement is true. Micelles are formed by the aggregation of surfactant molecules in an aqueous solution, and they typically adopt a spherical shape, with hydrophobic tails pointing inward and hydrophilic heads facing outward.
**Conclusion:** T

### Step 4: Analyze Statement (d)
**Statement:** Lyophilic sols are irreversible sols.
**Evaluation:** This statement is false. Lyophilic sols (sols where the dispersed phase has a strong affinity for the dispersion medium) are reversible; they can be re-dispersed after coagulation. In contrast, lyophobic sols are typically irreversible.
**Conclusion:** F

### Final Order of True (T) and False (F)
Based on the evaluations:
- (a) T
- (b) T
- (c) T
- (d) F

Thus, the correct order of initials is: T, T, T, F.