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1. Had they taken into account the weight before heating they would have made

less mistakes. 2. Thus, the deuterium, the nucleus of H2 could be considered to be

built up from a proton and a neutron. 3. Had the condenser been placed in a direct

current the current would have started flowing as though the condenser were not

present. 4. Were water allowed to run back into the generator an explosion might

result. 5. It is necessary that they should determine whether or not this inorganic

substance is contained in the sample to be analysed. 6. It is necessary that atomic

energy should be used only for peaceful purposes.7. A reliable device for neutron

storage could greatly simplify the procedure, so that only one detector would be

needed. 8. It is desirable that the determination of the effect of glass composition

should be made. 9. If no catalyst were employed in cracking, the process would be

called "thermal cracking 10. If the gas were colourless, we should not notice its

formation; we should have noticed the formation of this gas if it hadn't been

colourless. 11. If analytical balances were used the results would be much more

precise. 12. If air were a single compound the bubbles escaping from the solution

would have the same composition as those of undissolved air. 13. If the liquid were

placed between the plates of a condenser and an electric field applied, the molecules

would tend to orient themselves both .o positive and negative plates. 14. Had water

been purified carefully they wouldnt. repeat the experiment. Remember; water has to

be purified lest it should contain microbes. 15. If two liquids had been mutually

insoluble, neither one would have lowered the vapour pressure of the other. 16. It is

desirable that the sample should be weighed again as the weight does not confirm our

data. 17. If a crucible filled with pure arsenic were heated to a temperature above the

melting point of the arsenic, and the system were then allowed to cool, it would be

noted that the temperature would increase steadily with time. 18. If pure lead were

used the falling drops would solidify rather suddenly on reaching the temperature

327'C. 19. If we contemplated water in a glass, the water would appear optically

uniform. At any rate, we cannot discern any difference in the appearance of the water

at the bottom of the glass and on the surface.20. If there was no order in the way in

which atoms of different elements combine to form the molecules and crystals of

compounds, it would be necessary for us to - memorize one by one the formulas of

thousands of substances. 21. If an electron were to be removed from the sodium

atom, leaving only 10 electrons around the nucleus, the resulting partic1e would have

a positive charge, this particle composed of a sodium nucleus and 10 electrons, being

called a sodium ion. 22. If the absolute temperature were doubted, the speed of the

molecules would increase. 23. If some iodine crystals are put into a flask, which is

then stoppered and allowed to stand at room temperature it would soon be seen that

the gas in the flask becomes violet in colour, showing that a quantity of iodine evaporated.


1. Reaction appears to be almost instantaneous at room temperature. 2. To test

the validity of these assumption, we have to study the reactions of two representative

nitrones. 3. However, since the problems to be investigated cannot be solved even in

an idealized form by linear differential equation, the differential equation, which we

are to use wi.l have to be non-linear. 4. The system under investigation is considered

to be in a state of equilibrism, when all the co-ordinates are constant with respect to

the time. 5. Hence, the Young's model appears to be too simple and needs to be

modified to fit the present experimental findings. 6. He was always the first to take up

the most difficult problems and to solve them. 7. One can hardly expect a true

scientist to work in the limits of one narrow field. 8. To find the length of an object

was a very difficult task and we had to carry out a lot of experiments. 9. Once the

distribution of gas velocities has been calculated, the final step is to determine the

nature and extent of the separation of uranium isotopes in the gas. 10. The only

practical way to detect a slow neutron is to allow it to be absorbed by a nucleus. 11.

Since we are to deal very largely with ions in our reactions it is necessary to

remember that the solution should be diluted. 12. The science of organic chemistry is

a very extensive one, and the selection of a small number of facts to e resented in

these two chapters has to be restricted. 13. Urea was ong considered to be the first organic

compound, it is known first to be produced in the laboratory. 14. Nylon is

known to have been made in several different firms; the first to be produced

commercially was the most important. 15. The order of some reactions is known to

have been determined by measuring the time required for a constant fraction of

reaction to occur. 16. Every living organism can be shown to be made of cells. 17.

Since the enzyme concentration in living cells is likely to be difficult to estimate we

often speak about their activities. 18. Over the past few years much attention is

known to have been given to unimolecular reactions driven by lasers. It has also been

stated lasers to find wide application in chemical industry. 19. This assignment is too

difficult to be carried out at once, it is to take at least ten days or even more. 20. In

qualitative analysis we have to deal with the amphoteric characteristics of the hydroxides.

2l. Since we are to deal very largely with ions in our reactions it is necessary to

remember that the solution has to be diluted.to su a degree that the substance is largly

ionized. 22. The absorption of a quantum of visible or ultraviolet radiation could be

exected to alter the state of excitation electronic structure of an atom or a molecule.



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Date: 2015-12-17; view: 1586

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