A buzz in the world of chemistry Reading Answers

Oct 9, 2025

A Buzz in the World of Chemistry Reading Answers contains 13 questions and belongs to the assessment system of the IELTS General Reading test. A Buzz in the World of Chemistry Reading Answers must be answered within 20 minutes. In this IELTS reading section, question types include: Complete the text below, Write your answer A-F in the order, and complete the flow chart below.

A Buzz in the World of Chemistry Reading Answers offers a comprehensive overview of Combinatorial chemistry, which is a branch of synthetic organic chemistry that creates large libraries of compounds using automated solid-phase methods for drug and material discovery. It revolutionizes research by enabling rapid synthesis and screening, meeting modern pharmaceutical and biotechnology demands. To practice similar reading tests, candidates can refer to the IELTS Reading Practice Test section.

Check: Get 10 Free Sample Papers
Check: Register for IELTS Coaching - Join for Free Trial Class Now

Topic:

A.For the past few years, one of the buzz terms in the pharmaceutical, agrochemical and biotechnology industries has been 'combinatorial chemistry'.

Surf the net and find thousands of references to it. Read any of the general science weeklies, such as nature or new scientist, and every few issues, another worthy author is going to save the 21st century from everything nasty with this miraculous technology. Some of the more specialist journals have even devoted whole issues to reviewing combinatorial chemistry.

B.These reviews all have the same format. First, there is the section from research and development director of a major chemical company, a person who was not worked at the bench for years, if not decades. This is filled with business speak; the jargon keeps the shareholder happy and makes them proud to own a bit of something at the forefront of science. Section two is from a director of a venture capital funded synthetic chemistry company located on a green field side, probably in a protacabin, or, perhaps, in a new business park, rent free for the first five years from the local authority of a small town no one has heard of. He discusses the molecular modeling packages that they are using to build 'virtual' libraries containing millions of compounds. The third section is by someone who, in fact, practices combinatorial chemistry and who developed automated system to do the syntheses and to assay the products.

They can probably synthesise a few thousands compound per week.

C.We know that organic chemistry is the chemistry of carbon, biochemistry the chemistry of life and physical chemistry the application of physics to chemical behaviour. What then is combinatorial chemistry?

D.Combinatorial chemistry is the branch of synthetic organic chemistry. We all remember mathematics classes at school just before end of the term when we were given silly sums to do: How many waves can five differently coloured beads are arranged on a string? (120). Maths teachers call these permutation and combination problems; hence, combinatorial chemistry.

E.After the development of solid phase peptide synthesis in the 1960s by Merrifield, soon synthetic peptide chemists were also doing permutation and combination sums. There are 20 naturally occurring amino acids, the building blocks of peptides and proteins, the workhouse molecules of life. How many ways can these be arranged, or chemical bonded, to synthesise novel peptides which might be put to any number of uses in the pharmacy? If we take just one molecule of each of the 20 amino acids and join the together to form a peptide, we find that we can arrange these in 20! Or 2.432902008177*1018 ways. Nature knows no such restraint; it can use multiple copies of each amino acid, and so can synthesise 2020 or 1.048576*1026 twenty amino acid peptides. Proteins contains hundreds of amino acids. The number of possible sequences are truly innumerable!

F.They become even more so when one considers the other polymeric molecules of life: the lipids, carbohydrates and nucleic acids. Classically trained synthetic chemists strive for purity. One remembers twelve years ago chemist synthesizing a 20 residue peptide. He went of the lab, was ever so busy, producing a different high performance liquid chromatography (HPLC) trace every few days to show his biologist customers how the reactions were progressing. A few months after the request was placed, the biologists were given a few milligrams of their desired peptide and half a rain forest worth of HPLC printout!

G.That was fine when only one product was sought. Now the demand is for thousands of products to satisfy the automated high- through-put screening system employed by the major pharmaceutical companies. How can this be achieved?

H.let us consider solid phase synthesis strategies. In these, the compound of interest is synthesised on a solid support, a resin bead. These beads are typically 100 microns in diameter made from cross-linked polyvinyl; benzene or polyethylene glycol polymers.

I.Using the Tea-bag method, developed by Houghten in the 1980s, typically about 100 mg of the 100 micron beads are put into polypropylene mesh sacs which have a 75 micron mesh size. These are thermally sealed closed and the synthesis takes place on the resin beads with the sac. During the synthesis reaction cycles, the sacs are transferred from reagent pot to pot in sequence, and at the end of the synthesis, the product is cleaved off the bead, characterized and purified as need be. Using this strategy, one need to use a separate sac for each compound to be synthesized and automated systems have now been developed for multiple sac manipulation.

J.The sensitivity of compound analytical techniques has developed apace with the technology, and whereas, in the 1980s, one required several millimoles of product to characterize, now this can be done with femtomoles or in some cases attomoles (10-18moles)! Therefore, one need only recover product from 1 bead, about 2-3 picmoles. Automated systems are now being developed to synthesise on single magnetic beads using only2-3nanoliters of reagent per cycle. When the 'classical' Tea-bag strategy was developed, 100 milliliters per cycle were considered to be a phenomenal solvent cost-cutting exercise.

K.The development of high-the-put automated screening has demanded from synthetic chemistry large arrays or libraries of compound to satisfy the investment made in installing these systems. Will combinatorial chemistry be able to meet this demand? Are the synthesizes well enough developed to meet this? Peptide and oligonucleotide solid phase strategies have been well enough developed over the past 30 years. Will solution methods and other novel chemistries be able to keep apace? Can 'virtual' chemical be used to remedy 'real' problems? After all, we are living a real world.

Questions 14-19

Complete the text below, which is a summary of paragraphs A-E. Choose your answers from the word list and write them in boxes.

You may use each word only once.

HOW COMBINATORIAL CHEMISTRY BEGAN

Combinatorial chemistry as an (14)............

Answer: offshoot

Supporting statement: “Combinatorial chemistry is the branch of synthetic organic chemistry.”

Keywords: branch, synthetic organic chemistry, combinatorial chemistry

Keyword Location: Paragraph D, Line 1

Explanation: The passage explains that combinatorial chemistry developed as a branch of synthetic organic chemistry, making it an “offshoot” of that field.

of synthetic organic chemistry has been very much (15)......

Answer: in vogue

Supporting statement: “For the past few years, one of the buzz terms… has been ‘combinatorial chemistry.’”

Keywords: buzz term, combinatorial chemistry, recent years

Keyword Location: Paragraph A, Line 1

Explanation: The phrase “buzz term” implies that the subject is popular or fashionable, meaning it is “in vogue.”

in recent years, (16)...............

Answer: appearing

Supporting statement: “Read any of the general science weeklies… and every few issues, another worthy author is going to save the 21st century with this miraculous technology.”

Keywords: every few issues, author, article

Keyword Location: Paragraph A, Lines 2–3

Explanation: The description suggests that numerous articles are “appearing” in journals and magazines, showing frequent publication on the topic.

in a plethora of articles written by experts in the field. Moreover, all the reviews in specialist publications (17)............

Answer: usually follow

Supporting statement: “These reviews all have the same format.”

Keywords: reviews, same format, structure

Keyword Location: Paragraph B, Line 1

Explanation: The line indicates that reviews on combinatorial chemistry typically follow the same structure, hence they “usually follow” the same formula.

the same formula. But what about the origin of combinatorial chemistry? It comes from permutation and combination problems in mathematics (18).........

Answer: once

Supporting statement: “After the development of solid phase peptide synthesis in the 1960s…”

Keywords: after, solid phase peptide synthesis, development

Keyword Location: Paragraph E, Line 1

Explanation: The word “after” signifies that peptide synthesis occurred “once” solid phase methods were developed.

solid phase peptide synthesis was developed, synthetic peptide chemists started doing similar calculations as well. The 20 naturally occurring amino acids provided them with (19)......................

Answer: limitless

Supporting statement: “The number of possible sequences are truly innumerable!”

Keywords: innumerable, sequences, amino acids

Keyword Location: Paragraph E, Last line

Explanation: The word “innumerable” means countless or limitless, describing the vast number of possible amino acid combinations.

Possibilities.

Questions 20-24

Use NO MORE THAN THREE WORDS for each.

Look at paragraphs I and J which describe the Tea-bag method. Using the information in the passage, complete the flow chart below.

IN THE TEA-BAG METHOD

- special solid supports are placed in 20………………

Answer: polypropylene mesh sacs

Supporting statement: “About 100 mg of the 100 micron beads are put into polypropylene mesh sacs.”

Keywords: 100 mg, beads, polypropylene mesh sacs

Keyword Location: Paragraph I, Line 2

Explanation: The solid supports (resin beads) are placed inside polypropylene mesh sacs during the Tea-bag method.

- - which are then 21………………….. to close

Answer: thermally sealed

Supporting statement: “These are thermally sealed closed and the synthesis takes place…”

Keywords: thermally sealed, closed, sacs

Keyword Location: Paragraph I, Line 3

Explanation: The sacs are sealed using heat to prevent contamination and contain the beads during synthesis.

- Chemical bonding occurs on the solid supports, i.e. on the 22…………….

Answer: resin beads

Supporting statement: “The synthesis takes place on the resin beads within the sac.”

Keywords: synthesis, resin beads, within sac

Keyword Location: Paragraph I, Line 3

Explanation: The actual chemical bonding or synthesis happens on the resin beads that act as the solid supports.

- During the process, the sacs are moved from 23………………

Answer: reagent pot to pot

Supporting statement: “During the synthesis reaction cycles, the sacs are transferred from reagent pot to pot in sequence.”

Keywords: transferred, reagent pot to pot, synthesis

Keyword Location: Paragraph I, Line 4

Explanation: The sacs are moved from one reagent solution to another for each stage of the synthesis cycle.

- And, finally, the product is separated, characterized and 24………………… as required.

Answer: purified

Supporting statement: “At the end of the synthesis, the product is cleaved off the bead, characterized and purified as need be.”

Keywords: product, characterized, purified

Keyword Location: Paragraph I, Line 5

Explanation: The final step in the process involves separating and purifying the synthesized product.

Questions 25-27

Which three contributors are described by the writer?

Below is a list if the regular types of contributor to chemistry reviews. Write your answer A-F in the order.

A. A direct of s technology Business Park.

B. Someone who is from a major company and involved directly in research.

C. Someone who is involved in the new technology of combinatorial chemistry.

D. An amateur chemist who synthesizes thousands of compounds per week.

E. The director of a small obscurely located and investment funded operation.

F. An out-of-practice director of some major chemical enterprise.

Answer: F

Supporting statement: “There is the section from research and development director of a major chemical company, a person who was not worked at the bench for years, if not decades.”

Keywords: director, major chemical company, not worked for years

Keyword Location: Paragraph B, Lines 1–2

Explanation: This matches the description of an “out-of-practice director of some major chemical enterprise.”

Answer: E

Supporting statement: “A director of a venture capital funded synthetic chemistry company… located in a new business park, rent free for the first five years.”

Keywords: venture capital funded, business park, director

Keyword Location: Paragraph B, Lines 3–5

Explanation: This refers to a small, investment-funded operation described in option E.

Answer: C

Supporting statement: “The third section is by someone who, in fact, practices combinatorial chemistry and developed automated systems to do the syntheses.”

Keywords: practices combinatorial chemistry, automated system

Keyword Location: Paragraph B, Lines 6–7

Explanation: The person directly involved in practicing combinatorial chemistry matches description C.

Check IELTS reading samples: