Dragnet Verbal Reasoning Questions and Answers


Groundwater is usually free of contaminants and does not require filtration, but it often contain iron and other minerals that must be removed to soften the water. Hard water contain ions called calcium and magnesium which render it unsuitable for many purposes. When soap is used with hard water, it is precipitated by these ions to form scum, so that more soap is required to produce lather. Hard water is also undesirable in hot water systems because it deposits calcium Carbonate and calcium sulphate inside pipes and boilers. This is known as limescale. climate Ion-exchange is sometimes used to soften water. Zeolites or ion-exchange resins which release positive ions and take up, in exchange, is sometimes used to soften water. This involves zeolites or ion-exchange resins which releases positive ions and take up, in exchange, the calcium and magnesium ions of hard water. Another method of softening water is precipitation, where chemicals added to hard water combines with the calcium and magnesium ions to form insoluble precipitate that are easily removed.


36)

Which two of these statements must be true?

(True) The precipitate created by the addition of chemicals can be easily removed to leave behind softened water.
Very true – as seen in the last two lines of the passage

(False) The chemicals in hard water are dissolved during the process of precipitation
The passage tells us in the last sentence of the passage that the chemicals added combines with the calcium and magnesium to form INSOLUBE precipitate i.e undissolved precipitates

(Cannot say) The process of water softening is speeded up by combining calcium and magnesium ions with other chemicals
The idea presented above brings up the notion that water softening can take place on it’s own but the passage does not tell us, and so we cannot conclude

(True) The interaction of chemicals plays an important role in some methods of water softening
Very true – as seen in the last sentence of the passage
37)

Which two of these statements must be true?

(True) Hard water contains calcium and magnesium ions that are taken up by zeolites in the process of ion-exchange.
Line 10 – 12 states that zeolites or ion-exchange resins releases positive ions and take up, in exchange, the calcium and magnesium ions of hard water

(False) The process of water softening depends on the action of zeolites or ion-exchange resins
This is false because the passage presents precipitation as another method of softening hard water

(Cannot say) Softened water contributes to the formation of insoluble precipitates
The passage does not tell us anything on the above statement, it however tells us in the last sentence that Softening process of hard water causes the formation of insoluble precipitates that are easily removed.

(True) Calcium and magnesium ions in hard water are removed in the process of precipitation
Very true – as seen in the last two lines of the passage
38)

Which two of these statements must be true?.

(True) Limescale always accumulates inside heating systems which function with hard water
Very true – as seen in the first and second sentences of the second paragraph

(Cannot say) Pipes and boilers are affected by the composition of hard water
The passage states in the second paragraph that Hard water is also undesirable in hot water systems because it deposits calcium Carbonate and calcium sulphate inside pipes and boilers, but it does not tell us in exact term the effect of these deposits on pipes and boilers.

(True) The use of hard water in heating systems can lead to the build of limescale
Very true – as seen in the first and second sentences of the second paragraph

(Cannot say) The presence of calcium carbonate and calcium sulphate in hot water system can be countered by soft water
The passage does not say anything about this
39)

Which two of these statements must be true?

(Cannot say) The ion content of hard water is increased by the soap
This idea was never brought up in the passage, what the passage states is that When soap is used with hard water, it is precipitated by these ions to form scum, so that more soap is required to produce lather

(Cannot say) Greater volumes of hard water than soft water are required in order to produce lather
Such comparism was never made in the passage

(True) The production of lather is influenced by the ion level of hard water
Yes, there is a relationship between lather precipitation and ions. The passage states that “When soap is used with hard water, it is precipitated by these ions to form scum, so that more soap is required to produce lather

(True) Calcium and magnesium ions precipitate soap to produce scum
Line 4 of the passage states “When soap is used with hard water, it is precipitated by these ions to form scum”

Humans have hunted whales for thousands of years, but in the 18th and 19th centuries whaling became an important industry, due to high demand for whale oil. Even after industrialisation, whaling carried on at unsustainable levels and by the mid-twentieth century whale populations had severely declined. The International Whaling Commission (IWC) was established in 1946 to ensure the conservation of whales and to oversee the development of the whaling industry. In 1986, the IWC imposed a moratorium on commercial whaling to prevent the extinction of endangered whale species. As a result of the ban, whale stocks have recovered and thus some countries advocate the lifting of restrictions. Using loopholes in the moratorium, Japan, Norway and Iceland currently engage in commercial whaling and vigorously defend the practice as part of their cultural heritage. Anti-whaling activists, however, oppose whaling on ethical grounds. They argue that whales remain vulnerable, and that whales’ intelligence gives them intrinsic value.
So intense is the whaling debate that the IWC, which requires a 75% vote to overturn the ban, has reached a stalemate. Even within nations backing a return to commercial whaling the issue is divisive. Not only has demand for whale meat declined, whale-watching has become a popular tourist activity, and an end to restrictions could threaten this profitable industry.


40)

Which two of these statements must be true?

(False) Most countries advocate the lifting of the ban
The passage states that “SOME countries advocate the lifting of restrictions”

(True) Arguably, whales are more valuable alive than dead
Very true – because the last paragraph cites Whale watching as a lucrative industry

(False)About 75% vote is required to overturn the ban
The last paragraph states SPECIFICALLY that “a 75% vote is required to overturn the ban. About 75% could even be below 75%, but this is not what the passage states

(True) Demand for whale oil made whaling an important industry
The second line of the passage states that “whaling became an important industry, due to high demand for whale oil.

Similar CBTs


Popular CBTs