Q1 · June 2021 · 2 marks
In a Langmuir-type adsorption, a solid adsorbs 0.25 mg of a gas when the pressure of the gas is 50 bar and 0.2 mg of the gas at 20 bar pressure. The percentage of surface coverage at 50 bar is close to:
- (a) 75
- (b) 38
- (c) 57
- (d) 83
Show answer
Answer: (d)
Report an error in ABC26PH1444
Q2 · June 2021 · 2 marks
Liquid A has half the surface tension and twice the density of liquid B at 30°C. The contact angles of A and B are the same. If A rises 10 cm in a capillary, then the rise (in cm) of liquid B in the same capillary at the same temperature will be equal to
- (a) 60
- (b) 10
- (c) 40
- (d) 20
Show answer
Answer: (c)
Report an error in ABC26PH1445
Q3 · Dec 2019 · 2 marks
The order of a surface catalyzed unimolecular reaction, at very low and very high pressures of the reactant, would be, respectively
- (a) 0,0
- (b) 1,0
- (c) 0,1
- (d) 1,1
Show answer
Answer: (b)
Report an error in ABC26PH0219
Q4 · June 2019 · 2 marks
Above the critical micelle concentration (CMC), the option which correctly describes the variation of molar conductivity with increase in concentration of sodium dodecylsulphate in aqueous solution is
- (a) molar conductivity increases sharply, but the solution does not remain colloidal
- (b) molar conductivity decreases sharply, but the solution remains colloidal
- (c) molar conductivity decreases sharply and dissociation into monomers also occurs sharply
- (d) molar conductivity increases sharply with large loss of entropy The above critical Micelle concentration, the aggregation of molecules takes place to form Micelle resulting in the drastic decrease in molar conductivity. The size of aggregation is still in colloidal range.
Show answer
Answer: (b)
Report an error in ABC26PH1437
Q5 · Dec 2019 · 2 marks
A liquid of density 1.1 \mathrm{g\,cm^{-3}} climbs to a height of 5.0 cm when a capillary with internal radius of 0.2 mm is dipped into it. The surface tension (in \mathrm{N\,m^{-1}}) of the liquid is closest to
- (a) 0.05
- (b) 0.108
- (c) 0.018
- (d) 0.005
Show answer
Answer: (a)
Report an error in ABC26PH1438
Q6 · Dec 2019 · 2 marks
The order of a surface catalyzed unimolecular reaction, at very low and very high pressures of the reactant, would be, respectively
- (a) 0, 0
- (b) 1, 0
- (c) 0, 1
- (d) 1, 1
Show answer
Answer: (b)
Report an error in ABC26PH1439
Q7 · Dec 2019 · 2 marks
The correct statement about chemisorption is
- (a) Chemisorption results in multi molecular layer adsorption.
- (b) Chemisorption is reversible in nature.
- (c) Chemisorption has lower specificity than physisorption.
- (d) Chemisorption occurs due to formation of chemical bonds
Show answer
Answer: (d)
Report an error in ABC26PH1440
Q8 · Dec 2019 · 2 marks
The surface tension of dilute soap solution is lower than that of pure water because
- (a) soap molecules accumulate more at the surface than in the bulk solution.
- (b) soap molecules accumulate more in the bulk than on the surface.
- (c) the soap molecules aggregate uniformly in the bulk and the surface.
- (d) soap molecules form micellar structures at low concentration.
Show answer
Answer: (a)
Report an error in ABC26PH1442
Q9 · June 2017 · 2 marks
An intense purple colour (Plasmon band) is exhibited by a colloid consisting of spherical
- (a) silver particles of 10 mm diameter
- (b) silicon particles of 5 mm diameter
- (c) gold particles of 5 nm diameter
- (d) iron particles of 3 mm diameter
Show answer
Answer: (c)
Report an error in ABC26PH1435
Q10 · Dec 2016 · 2 marks
When 1 \times 10^{-5} \mathrm{~g} of a fatty acid (\mathrm{M}=602.3 \mathrm{~g} / \mathrm{mol}) was placed on water as a surface film, a monomolecular layer of area 100 cm 2 was formed on compression. The cross-sectional area (in \AA_{2} ) of the acid molecule is
- (a) 50
- (b) 100
- (c) 150
- (d) 200
Show answer
Answer: (b)
Report an error in ABC26PH1431
Q11 · June 2016 · 2 marks
When river water containing colloidal clay flows into the sea, the major cause of silting is
- (a) accumulation of sand at the bottom
- (b) flocculation and coagulation
- (c) decreased salinity of sea water
- (d) micellization
Show answer
Answer: (b)
Report an error in ABC26PH1434
Q12 · Dec 2015 · 2 marks
Stability of lyophobic dispersions is determined by
- (a) inter-particle electric double layer repulsion and intra-particle van der Waals attraction
- (b) inter-particle electric double layer attraction and intra-particle van der Waals repulsion
- (c) inter-particle excluded volume repulsion and intra-particle van der Waals attraction
- (d) inter-particle excluded volume attraction and intra-particle van der Waals repulsion Stability of lyophobic dispersions is determined by inter-particle electric double layer repulsion and intra-particle vander waals attraction
Show answer
Answer: (a)
Report an error in ABC26PH1429
Q13 · June 2014 · 2 marks
For the non dissociative Langmuir type adsorption of a gas on a solid surface at a particular temperature, the fraction of surface coverage is 0.6 at 30 bar. The Langmuir isotherm constant (in \mathrm{bar^{-1}} units) at this temperature is
- (a) 0.05
- (b) 0.20
- (c) 2.0
- (d) 5.0
Show answer
Answer: (a)
Report an error in ABC26PH1425
Q14 · June 2012 · 2 marks
Dispersion of a solid in a liquid, a liquid in a gas and a liquid in a liquid are respectively known as
- (a) Aerosol, emulsion, sol
- (c) Emulsion, sol, aerosol
- (b) sol, Aerosol, emulsion
- (d) Aerosol, sol, emulsion
Show answer
Answer: (b)
Report an error in ABC26PH1416
Q15 · June 2012 · 2 marks
A dilute silver nitrate solution is added to a slight excess iodide solution. A solution of AgI is formed whose surface adsorbs.
- (a) \mathrm{I^-}
- (b) \mathrm{NO_3^-}
- (c) \mathrm{Na^+}
- (d) \mathrm{Ag^+}
Show answer
Answer: (a)
Report an error in ABC26PH1417
Q16 · June 2012 · 2 marks
The adsorption of a gas is described by the Langmuir isotherm with the equilibrium constant K = 0.9 \mathrm{kPa^{-1}} at 25°C. The pressure (in kPa) at which the fractional surface coverage is 0.95, is
- (a) 1/11.1
- (b) 21.1
- (c) 11.1
- (d) 42.2
Show answer
Answer: (b)
Report an error in ABC26PH1419
ABC Chemistry
CSIR NETChemical Science Coaching
GATEChemical Science Preparation
IIT JAMM.Sc Entrance Coaching
CUET PGPost Graduate Entrance
Class 11 ChemistryLive online
Class 12 ChemistryLive onlineStudy LibraryPrevious year papers171 official papers · JAM, NET, GATE, CUETTopic-wise decks32 PDF + PPTX decks, freeBuild your own PDFChoose exam → topic → downloadStudy materialUnit-wise notes for the batchesTest papers 8–12School practice papersDreamer's QuizWeekly chemistry quizQuestions by topicRead online with verified answersSearchTopics, courses and articlesExam guidesSyllabus, pattern, eligibilityBlogChapter notes and PYQ analysisBooks by ABPeriodic table and data bookGreat Home TutorPh.DAboutContactBlogsQ&A▶️ YouTubeEnquiryBook a free demoCall +91 92121 42427