Category: Pulp & Paper Objective Questions

250+ TOP MCQs on Raw Materials and Answers

Pulp and Paper Multiple Choice Questions on “Raw Materials”.

1. _________ is the mixture of pulp, fillers, and other papermaking materials, and water.
a) PCC
b) Fillers
c) Stock
d) Dyes
Answer: c
Clarification: Stock’s the mixture (slurry) of pulp, fillers, andother papermaking materials, and water. Furnish’s the combination of all of the materials utilized to make paper .

2. _________ consists of paper trimmings and waste, paper not upto the level, and other paper that’s often re-used in the paper mill.
a) Broke
b) Stock
c) Fillers
d) PCC
Answer: a
Clarification: Broke consists of paper trimmings and waste, paper not upto the level, and other paper that’s often re-used in the paper mill. A mill producing more than 10-15 percent broke isn’t operating efficiently.

3. _________ are materials used to improvise the finished paper itself or aid in the papermaking process.
a) Stock
b) Fillers
c) Additives
d) Broke
Answer: c
Clarification: Additives are materials utilized to improvise the finished paper itself or aid in the process of papermaking.

4. Functional additives like dyes, internal sizing agents, adhesives to increase wet or dry strength, and fillers are used to improve or impart some qualities to the paper product.
a) True
b) False
Answer: a
Clarification: Functional additives like dyes, internal sizing agents, adhesives to increase wet or dry strength, and fillers are used to upgrade some qualities to the paper product and must be retained on the sheet to be effective.

5. Control additives like biocides, drainage aids, retention aids, pitch control agents, and de-foamers are added to upgrade the_________ but don’t directly affect the _________
a) Kraft process and product
b) Pulp extraction process and product
c) Paper making process and product
d) Lignin extraction process and product
Answer: c
Extraction: Control additives like biocides, drainage aids, retention aids, pitch control agents, and de-foamers are added to upgrade the papermaking process, but do not directly affect the product and aren’t necessarily retained on the product.

6. A lot of additives have different effects at the same time; for example, alum is required for rosin sizing under acid situations but also serves as a drainage and retention aid.
a) True
b) False
Answer: a
Clarification: A lot additives have several effects at the same time; for example, alum is required for rosin sizing under acid situation but also serves as a drainage and retention aid. Both types of additives are also added to the stock prior to paper making process.

7. _________ are expensive chemicals that must be utilized at exact levels, so they are usually metered into the system from +ve displacement metering pumps.
a) Liquid additives
b) Control additives
c) Broke
d) Furnish
Answer: a
Clarification: Liquid additives are the expensive chemicals that must be used at exact levels, so they are usually metered into the system from +ve displacement metering pumps.

8. Like most positive displacement pumps, the use of appropriate filters in front of the pump inlet to keep the pump from fouling by blocking the _________ valves in an open position.
a) Check
b) Gate
c) Global
d) Air pressure
Answer: a
Clarification: Like most positive displacement pumps, be sure to use appropriate filters such as a 10 mesh or finer screen in front of the pump inlet to keep the pump from fouling by blocking the check valves in an open position. Use a pump inlet line of at least 12 mm C.A. in.) for additives with viscosity above 100 cps.

9. It is often more effective to pump _________ ambient pressure. Use of flow measurement device of some sort to insure flow of each additive.
a) Below
b) Above
c) Equal
d) Till
Answer: b
Clarification: Use a flow measurement device of some sort to insure flow of each additive because it’s often more effective to pump above ambient pressure, a pressure gauge can be used with a pressurized output to give at least give a qualitative flow rate, which’s better than no indication of flow.

10. _________ is a paper filler and a coating pigment which is of excellent opacity and bright.
a) Talc
b) Clay
c) PCC
d) TiO2
Answer: d
Clarification: Anatasa and Rutile TiO2 is a product with excellent opacity and brightness. Their refractive indexes are 2.55 and 2.70 respectively.


>

250+ TOP MCQs on Sulphite Liquor Calculation and Answers

Pulp and Paper Multiple Choice Questions on “Sulphite Liquor Calculation”.

1. The concentration of chemicals in sulfite pulping are noted on an SO2 basis.
a) True
b) False
Answer: a
Clarification: Sulfite pulping’s carried out b/w pH 1.5 and 5, depending on the counterion to sulfite (bisulfite) and the ratio of base to H2SO3. The pulp’s in contact with the pulping chemicals for 4 – 14 hours and at temperature ranging from 130 to 160 °Celcius.

2. All chemical sulfite methods use nearly 80% chemical (SO2 basis) on a dry wood basis.
a) True
b) False
Answer: b
Clarification: All chemical sulfite methods use nearly 20% chemical (SO2 basis) on a dry wood basis.

3. The various salts of _________ acid are of central importance to the various sulfite-based processes. The chemistry of _________ acid as a function of pH is very important.
a) Hydrochloric
b) Hydrogen fluoride
c) Hydrogen bromide
d) Sulphurous
Answer: d
Clarification: The chemistry of sulfurous acid as a function of pH is very imp. The titration curve of H2CO3, the first proton’s a moderately strong acid and titrates along with any strong acids present.

4. The _________ equation could not be utilized for this part of the titration curve since the H2CO3 ionizes appreciably, thereby reducing the conc. of H2CO3 and changing the ratio of acid to conjugate base significantly.
a) Kennedy
b) Henderson-Hasselbalch
c) Jhonty-Miller
d) Kraft-Hammer
Answer: b
Clarification: The Henderson-Hasselbalch eq. could not be utilized for this part of the titration curve since the H2CO3ionizes appreciably, there by reducing the conc. of H2CO3 and changing the ratio of acid to conjugate base significantly.

5. _________ is a moderately strong acid. It’ll react completely with any of the 5 common hydroxides utilized in sulfite cooking.
a) Sulphurous acid
b) Hydrochloric acid
c) Sulphuric acid
d) Nitric acid
Answer: a
Clarification: Sulfurous acid is a moderately strong acid. It will react completely with any of the 5 common hydroxides used in sulfite cooking. The form of the react. is independent of the base and occurs in 2 steps if enough base is present.

6. Derive the gravimetric factor for converting Ca(HSO3)2 to SO2.

a) 0.634g SO2
b) 1.254g SO2
c) 9.325g SO2
d) 40.456g SO2
Answer: a
Clarification: 1 mole of Ca(HSO3)2 gives two moles of SO2: Ca(HSO3)2 andrarr; 2SO2 + Ca(OH)2

Therefore

1g Ca(HSO3)2 x (2 mol SO2) / (1 mol Ca(HSO3)2) x (1 mol Ca(HSO3)2) / (202.21g Ca(HSO3)2) x (64.06 SO2) / (1 mol SO2) = 0.634g SO2

7. The various salts of _________are of central importance to the various sulfite-based processes. The chemistry of sulfurous acid as a function of pH is very imp.
a) Chlorine
b) Sulphur
c) Sulfurous acid
d) Calcium
Answer: c
Clarification:The various salts of H2SO3are of central importance to the various sulfite-based processes. The chemistry of sulfurous acid as a function of pH is very imp.

8. Fill in the blank.
MOH + H2SO3andrarr; __________+H2O
a) M2SO3
b) MHSO3
c) No react
d) SO4
Answer: b
Clarification: Sulfurous acid’s a moderately strong acid. It’ll react completely with any of the 5 common hydroxides used for sulfite cooking. The form of the reaction is independent of the base and occurs in 2 steps if enough base is there.

9. What is the name of the
MOH + MHO3andrarr; ______+H2O
a) M2SO3
b) MHSO3
c) No react
d) SO4
Answer: b
Clarification: Sulfurous acid’s a moderately strong acid. It’ll react completely with any of the 5 common hydroxides utilized in sulfite cooking. The form of the reaction is independent of the base and occurs in 2 steps if enough base is there.

10. The higher this ratio, the less _________ decrement is predicted when cooking to a specified kappa number
a) lignin content
b) pulpwood
c) groundwood
d) cellulose viscosity
Answer: d
Clarification: Ratio of H-factor to G-factor rates at various temperatures. The higher this ratio, the less cellulose viscosity decrement is predicted when cooking to a specified kappa number


>

250+ TOP MCQs on Surfactants and Answers

Pulp and Paper Multiple Choice Questions and Answers (MCQs) on “Surfactants”.

1. _________are surface-active agents that aggregate near or have a strong effect on modifying the interface b/w 2 materials.
a) Carboxylate
b) Tween
c) Ampholytic elements
d) Surfactants
Answer: d
Clarification: This occurs because of their dual nature: hydrophobic and hydrophilic. It’s a substance which tends to decrement the surface tension of a liquid in which it’s dissolved in it.

2. The hydrophilic moiety may be anionic, cationic, ampholytic, or non-ionic not depending on the type of charge(s) carried, if any.
a) True
b) False
Answer: b
Clarification: The hydrophilic moiety may be anionic (carboxylate, sulfate, or phosphate), cationic ,ampholytic, or nonionic (Span®, Tween®, Triton®) depending on the type of charge(s) carried, if any.

3. Anionic surfactants are generally less expensive than cationic ones, though the latter sometimes have biocidal action.
a) True
b) False
Answer: a
Clarification: In the anionic surfactants, the carboxylate group in soap is replaced by a sulfonate or as the hydrophilic component. The corresponding Ca and Mg salts are more soluble in H2O than the Ca and Mg salts of carboxylic acids.

4. The Span materials tend to be less water soluble than the _________materials. The same material could be a detergent, and a wetting agent.
a) Carboxylate
b) Tween
c) Ampholytic elements
d) Surfactants
Answer: d
Clarification: The Span materials tend to be less water soluble than the Tween materials. Surfactants are often known acc. to their use. The same material could be an emulsifier, or a dispersant.

5. The _________ of surfactants depends the most crucial factor that is strong water—water interaction, the hydrophobic effect.
a) CMC
b) Micelle
c) Polarity
d) Non-polarity
Answer: a
Clarification: This was discovered by Shaw in 1980. The nonpolar—nonpolar interaction in the centre of the micelle doesn’t provide the thermodynamic energy required for micelle formation. .

6. What is the type of hexahydric alcohol?
pulp-paper-questions-answers-surfactants-q6
a) Tween
b) Span
c) Triton
d) Multi-cyclic
Answer: b
Clarification: A member of the mannitol-sorbitol-dulcitol sugar group; isomer of C6H8(OH)6.

7. What is the type of hexahydric alcohol?
pulp-paper-questions-answers-surfactants-q7
a) Tween
b) Span
c) Triton
d) Multi-cyclic
Answer: a
Clarification: This comes under the category of mannitol-sorbitol-dulcitol sugar group; isomer of C6H8(OH)6.

8. What is the type of hexahydric alcohol?
pulp-paper-questions-answers-surfactants-q8
a) Tween
b) Span
c) Triton
d) Multi-cyclic
Answer: c
Clarification: A member of the mannitol-sorbitol-dulcitol sugar group; isomer of C6H8(OH)6.

9. What is the type of hexahydric alcohol?

CH3C(CH3)2CH2C(CH3)2

n = 9 for octoxynol

a) Tween
b) Span
c) Triton
d) Multi-cyclic
Answer: c
Clarification: This belongs to the mannitol-sorbitol-dulcitol sugar group; isomer of C6H8(OH)6.

10. Many surfactants that form micelles have a solubility below their C.M.C. Thus at a certain temperature, known as the _________ point, the solubility increases dramatically since the micelles are quite soluble.
a) Mars
b) Kraft
c) Kraffin
d) Curtis
Answer: c
Clarification: This belongs to the mannitol-sorbitol-dulcitol sugar group; isomer of C6H8(OH)6.


>

250+ TOP MCQs on Tristimulus Systems and Answers

Pulp and Paper Questions and Answers for Aptitude test on “Tristimulus Systems”.

1. Since there are 3 types of color sensors in the human eye, it should be possible to define color by 3 coefficients corresponding to the primary colors.
a) True
b) False
Answer: a
Clarification: Trichromaticism is the condition of possessing 3 self-supporting channels for conveying color information, derived from the 3 various cone types. The organism’s retina contains 3 types of color receptors with various absorption spectra.

2. Any color of any brightness could then be plotted on a 3—dimensional coordinate system, sometimes known as a __________
a) Color space
b) Dimensions
c) String
d) Munsell
Answer: a
Clarification: The exact wavelengths of these primary colors must be agreed upon and are the basis of the coefficients. It’s also known as the color model and is an abstract mathematical model which simply describes the range of colors as tuples of number’s, typically as 3 or 4 values or color components.

3. If one ignores brightness, then a color plane that intersects through the space; such a diagram is known as chromaticity chart and takes into account hue and saturation.
a) True
b) False
Answer: a
Clarification: Chromaticity is an objective specification of the quality of a color listless of its luminance. It consists of 2 independent parameters, often specified as hue and colorfulness, where the latter is alternatively known as saturation, chroma, or intensity.

4. The __________ is a non-quantitative 3 dimensional system for plotting colors.
a) Munsell
b) Gabriel
c) John
d) Paul
Answer: a
Clarification: It was specifically derived such that there is uniform spacing of perception. In other words, the distance required such that the observer could recognize 2 separate shades is about the same throughout the system. The value correlates with the brightness from black to perfect diffuse reflectance.

5. The 1st quantitative tristimulus system was formed by the __________ which defines the internationally accepted standard observer, utilized in the other systems.
a) CIE
b) CIA
c) CIS
d) CIM
Answer: a
Clarification: It’s the international authority on light, illumination, color, and color spaces. It was established in 1913 as a successor to the Commission Internationale de Photométrie and is today based in Vienna, Austria.

6. Who is the president of International Communication on Illumination?
a) Martin Scorsese
b) Yoshihiro Ohno
c) Stanley Kubrick
d) Alfred Hitchcock
Answer: a
Clarification: As of 2015, the president is Yoshiro Ohno from United States.

7. If monochromatic green light of wavelength 520 nano meter is mixed with various parts of white light the line is produced that goes from 520 nano meter to __________ light. This line accounts to various shades of the same hue.
a) Red light
b) Green light
c) Pink light
d) Orange light
Answer: b
Clarification: This line corresponds to various shades of various excitation purities of the same hue of dominant wavelength. A color, therefore, could be described by its dominant wavelength and excitation purity or its x and y values.

8. The chromaticity diagram is a plot of x and y values. The data are plotted every 10 nm from 380 nano meter to 720 nano meter; plotting every 1 nm would have made the curve smoother.
a) Monochromaticity
b) Chromaticity
c) Blindness
d) Transparency
Answer: b
Clarification: The C.I.E. xyz color space was deliberately designed so that the Y parameter was a measure of the luminance of a color. The chromaticity of a color was then specified by the 2 derived parameters x and y.

9. __________ values could be obtained by the comparison method where the color is matched by mixing 3 primary standards until visual observation gives a match, spectrophotometric analysis, or utilize of trichromatic methods employing analysis with 3 separate filters.
a) Chromaticity
b) Kubelka
c) Tristimulus
d) Black body
Answer: c
Clarification: Any color which could be produced by the primary colors blue, green, and red could be written:
where Blue, Green, and Red could be considered to be unit values for Blue, Green, and Red are the magnitudes or relative intensities of those primaries and are known as tristimulus values. Note that the unit values associated with Blue, Green, and Red are of various size in physical power units (watts) because the sensitivity of the eye will be various for the various primary colors.

10. __________ systems, these systems have to utilize efficient encoding of information because their transmissions have limited bandwidth during broadcast.
a) TV
b) Video color
c) Grey body
d) Red body
Answer: b
Clarification: Also, they must be compatible with black and white systems. This point is mentioned because the utilization of video based color is crucial in computer vision and other techniques, which will have more importance to the industry in the future.


To practice all areas of Pulp and Paper for Aptitude test, >

250+ TOP MCQs on Wood and Fibre Physics and Answers

Pulp and Paper Multiple Choice Questions on “Wood and Fibre Physics”.

1. The equilibrium moisture content of wood or wood pulp depends on the temperature and relative humidity of the atmosphere surrounding the specimen.
a) True
b) False
Answer: a
Clarification: Wood and paper are hygroscopic materials, when fully dried they absorb water vapor from the atmosphere. The equilibrium moisture content of wood or wood pulp depends on the temperature and atmosphere’s humidity surrounding the specimen.

2. What is the full form of FSP?
a) Fiber suction point
b) Fiber soft point
c) Fiber saturation parcel
d) Fiber saturation point
Answer: d
Clarification: The fiber saturation point represents the moisture content of the ligno cellulose material such that additionally adsorbed water is not chemically absorbed to the wood.

3. Wood shrinks and swells as a function of ____________
a) Stress
b) Shear stress
c) Strain
d) Moisture content
Answer: d
Clarification: It is due to the function of moisture content. Above the fiber saturation point there will be no change in wood dimensions according to the moisture content.

4. At low humidities the equilibrium moisture content will be lower.
a) True
b) False
Answer: a
Clarification: At low humidities the equilibrium moisture content will be lower. Chemically absorbed water requires additional energy to remove it from wood beyond the water’s heat of vaporization.

5. What increases the strength of the paper?
a) Lignin
b) Hemicellulose
c) Fiber
d) Lignocellulose
Answer: b
Clarification: The fibers of paper are held together by hydrogen bonding of the hydroxyl groups of cellulose and hemicellulose.

6. What decreases the strength of the paper?
a) Lignin
b) Hemicellulose
c) Fiber
d) Lignocellulose
Answer: a
Clarification: Lignin is not able to form H bonds, and results in decrement in strength of paper.

7. What could increase the fiber surface area?
a) Decrease inter-fiber bonding
b) Increase inter-fiber bonding
c) Decrease intra-fiber bonding
d) Increase inter-fiber bonding
Answer: b
Clarification: Factor which increment in fiber surface area is by increasing inter-fiber bonding.

8. Wood taken at room temperature and 99% relative humidity will have how much moisture content approaching?
a) 90%
b) 99%
c) 30%
d) 1%
Answer: c
Clarification: This occurs at about 30% MC (OD) (at room temperature) in wood.

9. Uneven grain orientation may cause severe warping or __ of lumber and furniture is prone to shrinkage as the wood dries.
a) Fracture
b) Welding
c) Brazing
d) Cropping
Answer: a
Clarification: Uneven grain orientation may cause warping or fracturing of lumber and the furniture due to tremendous stresses that could develop from uneven shrinkage as wood dries.

10. __________ bonding holds ligo cellulose fibers together in paper.
a) Sulfate
b) Hydrogen
c) Halogen
d) Phosphate
Answer: b
Clarification: The strength of R-OH—R-OH hydrogen bonding is 3 – 4kcal/mol. This is relatively as compared to covalent bonds.


>

250+ TOP MCQs on Pulp Bleaching and Answers

Pulp and Paper Multiple Choice Questions on “Pulp Bleaching”.

1. Bleaching is the treatment of wood (and other lignocellulosic) pulps with chemical agents to decrease their brightness.
a) True
b) False
Answer: b
Clarification: Bleaching is the treatment of wood (and other lignocellulosic) pulps with chemical agents to increase their brightness.

2. Bleaching of chemical pulps is achieved by lignin addition.
a) True
b) False
Answer: b
Clarification: Bleaching of chemical pulps is achieved by lignin removal.

3. _________ removal in chemical pulps leads to higher fiber-fiber bonding strength in paper, but the strong chemical pulps decrement in the length of cellulose molecules, resulting in weaker fibers.
a) Softwood
b) Hardwood
c) Lignin
d) Pulp
Answer: c
Clarification: Lignin removal in chemical pulps leads to higher fiber-fiber bonding strength in paper, but the strong chemical pulps decrement in the length of cellulose molecules, resulting in weaker fibers.

4. Bleaching mechanical pulps is called _________ to distinguish it from bleaching of chemical pulps.
a) Brightening
b) Bloating
c) Blackening
d) Branding
Answer: a
Clarification: Bleaching mechanical pulps is called brightening to distinguish them from the bleaching of chemical pulps.

5. Brightness is a term used to describe the _________ of pulp or paper, on a scale from 0 to 100.
a) Whiteness distribution
b) Whitness obstructivness
c) Coquettes
d) Bleach
Answer: a
Clarification: Brightness is a term used to describe the whiteness distribution of pulp or paper, on a scale from 0 to 100.

6. _________ is the yellowness of pulps on exposure to air, light, heat, and fungi due to modification of residual lignin forming chromophores.
a) Colour reversion
b) Colour addition
c) Oxidation
d) Exposure
Answer: a
Clarification: Colour reversion is the yellowness of pulps on exposure to air, light, heat, and fungi due to modification of residual lignin forming chromophores.

7. _________ pulps are susceptible to colour reversion.
a) Chemical
b) Mechanical
c) Dithionite
d) Hydrousulfite
Answer: b
Clarification: Mechanical pulps are particularly susceptible to colour reversion, though chemical pulps may experience this when exposed to high temperatures.

8. _________ pulps are not susceptible to colour reversion.
a) Chemical
b) Mechanical
c) Dithionite
d) Hydrousulfite
Answer: b
Clarification: Mechanical pulps are particularly susceptible to colour re-version, though chemical pulps may experience this when they are exposed to high temperatures.

9. Bleaching stages are carried out consistencies for pulp bleaching are from _________%.
a) 8-10
b) 3-20
c) 3-10
d) 4-15
Answer: b
Clarification: Bleaching stages are carried out under consistencies from 3-20%. Higher consistencies of 10-20% are used with chemicals such as oxygen, peroxide, and HOCl, which react with lignin slowly.

10. Higher bleaching stages are carried out in consisitencies of range____________
a) 8-10
b) 10-20
c) 15-20
d) 3-10
Answer: b
Clarification: Bleaching stages are carried out consistencies from 3-20%. Higher consistencies of 10-20% are used with chemicals such as oxygen, peroxide, and hypochloride, which react with lignin slowly.


>