Pulp & Paper Questions and Answers – Selected Reactions of Carbohydrates

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This set of Pulp and Paper Multiple Choice Questions and Answers (MCQs) focuses on “Selected Reactions of Carbohydrates”.

1. Acid hydrolysis becomes important in the pulp and paper industry whenever we process wood fibers below pH 2 or so at elevated temperatures.
a) True
b) False
View Answer

Answer: a
Explanation: Acid hydrolysis becomes important in the pulp and paper industry whenever we process wood fibers below pH 2 or so at elevated temperatures.

2. If one treats _________ with 6 % w/w aqueous sulfuric acid under reflux, glucose is obtained in high yield with little secondary decomposition.
a) Cellulose
b) Fructose
c) Starch
d) Lignin
View Answer

Answer: a
Explanation: If one treats cellulose (which has been swelled in 72 % w/w sulfuric acid at room temperature) with 6 % w/w aqueous sulfuric acid under reflux, glucose is obtained in high yield with little secondary decomposition.

3. If _________ are treated with strong acid such as 20% sulfuric acid at high temperatures, they are first hydrolyzed to the component _________
a) Polysaccharides, monosaccharides
b) Monosaccharides, polysaccharides
c) Fructose, cellulose
d) Lignin, pulp
View Answer

Answer: a
Explanation: If polysaccharides are treated with strong acid such as 20% sulfuric acid at high temperatures, they are first hydrolyzed to the component monosaccharides.
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4. One can reduce the reducing end of mono- or polysaccharides by using sodium borohydride (NaBH4) under _________ conditions at room temperature.
a) Acidic
b) Basic
c) Alkaline
d) Neutral
View Answer

Answer: c
Explanation: One can reduce the reducing end of mono- or polysaccharides by using sodium borohydride (NaBH4) under alkaline conditions at room temperature.

5. Under conditions of dilute alkali (perhaps 0.1 M NaOH at 100°C) _________ will slowly undergo a reaction that causes C-2 epimerization (a change in configuration of the second carbon atom).
a) Polymers
b) Polysaccharides
c) Monosaccharides
d) Fructose
View Answer

Answer: c
Explanation: Under conditions of dilute alkali (perhaps 0.1 M NaOH at 100°C) monosaccharides (and the reducing group of polysaccharides) will slowly undergo a reaction that causes C-2 epimerization (a change in configuration of the second carbon atom).

6. What is the name of the question mark area?
Dilute OH- undergo reaction that causes C-2 epimerization
a) 25% H2SO4, Reflux
b) 6% H2SO4, Reflux
c) Dilute OH-
d) Maximum Heat
View Answer

Answer: c
Explanation: Under conditions of dilute alkali (perhaps 0.1 M NaOH at 100°C) monosaccharides (and the reducing group of polysaccharides) will slowly undergo a reaction that causes C-2 epimerization (a change in configuration of the second carbon atom)

7. What is the name of the question mark area?
25% H2SO4, Reflux undergoes decomposition
a) 25% H2SO4, Reflux
b) 6% H2SO4, Reflux
c) Dilute OH-
d) Maximum Heat
View Answer

Answer: a
Explanation: The reaction of hexoses, or polymers of hexoses such as cellulose, starch, and glucomannans, produces 5- (hydroxymethyl)-2-fiirfiiral that is not volatile and undergoes decomposition to levulinic acid and numerous other compounds.
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8. What is the name of the question mark area?
25% H2SO4, Reflux of hexoses
a) 25% H2SO4, Reflux
b) 6% H2SO4, Reflux
c) Dilute OH-
d) Maximum Heat
View Answer

Answer: a
Explanation: The reaction of hexoses, or polymers of hexoses such as cellulose, starch, and glucomannans, produces 5- (hydroxymethyl)-2-fiirfiiral that is not volatile and undergoes decomposition to levulinic acid and numerous other compounds.

9. What is the name of the question mark area?
Find the 72 % w/w sulfuric acid from the given diagram
a) 25% H2SO4, Reflux
b) 6% H2SO4, Reflux
c) Dilute OH-
d) Maximum Heat
View Answer

Answer: b
Explanation: If one treats cellulose (which has been swelled in 72 % w/w sulfuric acid at room temperature) with 6 % w/w aqueous sulfuric acid under reflux, glucose is obtained in high yield with little secondary decomposition.
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10. What is the name of the question mark area?
Find the secondary decomposition from the given diagram
a) 25% H2SO4, Reflux
b) 6% H2SO4, Reflux
c) Dilute OH-
d) Maximum Heat
View Answer

Answer: b
Explanation: If one treats cellulose (which has been swelled in 72 % w/w sulfuric acid at room temperature) with 6 % w/w aqueous sulfuric acid under reflux, glucose is obtained in high yield with little secondary decomposition.

Sanfoundry Global Education & Learning Series – Pulp and Paper.
To practice all areas of Pulp and Paper, here is complete set of 1000+ Multiple Choice Questions and Answers.

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Manish Bhojasia - Founder & CTO at Sanfoundry
Manish Bhojasia, a technology veteran with 20+ years @ Cisco & Wipro, is Founder and CTO at Sanfoundry. He lives in Bangalore, and focuses on development of Linux Kernel, SAN Technologies, Advanced C, Data Structures & Alogrithms. Stay connected with him at LinkedIn.

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