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Q. 2. A piece of sulphur at one end of a balance beam is in equilibrium

with a piece of brass at the other end. How will the horizontality of the beam be affected when (1) the brass alone, (2) the

whole system--beam, brass and sulphur-is immersed in water! Usually done correctly. Q. 3. A railway train is moving round a circle with uniform velocity,

What are the forces which act upon it? Why must the outer

rail be raised above the inner ? Not more than five candidates realised that the centripetal force is exerted upon the train by the rails. This force was described as "pulling the train from the centre of the curve.”. The statement that inertia was one of the forces was frequent. No one knew exactly the effect of elevation of the outer rail. Most stated only that it was there to prevent the train running off the line.

Q. 4. What is meant by the energy of a swinging pendulum? Is the

energy the same when the bob is at the top as when it is at the

bottom of its swing? If not, how do they differ? Many knew that the energy was sometimes kinetic and sometimes potential ; but the names were confused, and very few knew that the sum of the two is nearly constant throughout the swing.

B.

Q. 5. Explain how the fixed points are marked on the stem of a

thermometer. What is the effect on the indication of a thermometer immersed in boiling water of adding some common

salt to the water ? A good many omitted to say that the ice should be melting. One or two candidates referred to the facts that the ice should be pure, and that the barometer should be read in the case of the boiling point Q. 6. It is possible to extioguish the flame of a candle by passing over

it (without touching the wick) a short coil of thick copper wire.

Explain why the candle is extinguished ? Most of the candidates knew the general lines of the explanation ; but many answers were incomplete in the respect that the necessity for the temperature to be above a certain value for combustion to continue was not stated.

Q. 7. If you look at a telegraph post through a slab of glass held some

distance from the eye you notice that the part of the post seen through the glass varies in position as the glass is rotated.

Draw a picture to illustrate this effect, and explain it. Very seldom attempted.

Q. 8. A dark blind covers the window of a room so that light only

enters by a narrow horizontal chink at the bottom. How would you hold a glass prism so as to see the chink through the prism, and what would the appearance be like? Draw a picture to

illustrate your answer. There were a few incomplete answers.

C.

Q. 9. Describe any methods you are acquainted with for preparing

hydrogen. What are its physical and chemical properties? Better done than any of the other questions. The commonest mistake was confusion of the physical and chemical properties.

Q. 10. What is “common salt”? What are its properties? What

experiments would you make to ascertain its nature ? Only a few knew how to show that salt contains sodium and chlorine. Q. 11. What would be the effect of putting into an oven and raising to

a high temperature, (1) wood, (2) iron, (3) marble, (4) washing soda? Would the results be the same if the substances were

heated in a Bunsen flame ? Many gave only physical effects, e.g. change of temperature, colour and state ia the case of iron, and most of the answers were incomplete. Q. 12. How does spring water generally differ from rain water? Why is

pure rain water not pleasant to drink? How can it be made

more palatable ? It was sometimes stated that the soil acted as a filter in the case of spring water. Softness and hardness were frequently mentioned without being understood, e.g., rain water was stated to have a soft taste.

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Results : 1st Class, 759 ; 2nd Class, 671 ; Failed, 616; Total, 2,046. There is a consensus among those who have read the papers that, on the whole, they represent a marked improvement on those of former years. There is much less of the hopeless rubbish which was at one time so characteristic of the answers in this stage. But while on the whole satisfactory, the papers seem to indicate a certain amount of neglect of some fundamental subjects to which the attention of the teachers ought to be directed. Of these, the most important is represented by Q. 4, which asks for an explanation why it is wrong to represent the composition of atmospheric air by a formula, such as N O. For years past the Examiners have been endeavouring to suppress this practice, which was at one time very common, and was evidently the result of widespread erroneous teaching. Even now the answers to this question show, in a large proportion of cases, that the students do not apprehend correctly the nature of the error involved in the use of a formula. It seems to be thought that the formula is to be objected to on the ground that it ignores the small amounts of water vapour, carbon dioxide, and other gases present, along with the oxygen and nitrogen, and therefore does not represent truly the composition of atmospheric air. It ought to be made more clear to them that the fundamental mistake lies in using a formula which implies definite chemical composition, and the existence of a definite compound with definite properties, rather than a mere mixture of two things which are not present in fixed and invariable proportions, and, being merely mechanically mixed together, are capable of being separated by merely mechanical processes. More care should be taken by the teachers to explain the meaning and application of chemical formule.

Q: 12 consists of an easy problem in the calculation of weights and volume . Rather unexpectedly, this was attempted by a smaller proportion of the candidates than usual, and by them often unsuccessfully.

Attention should be drawn to the fact that there is a tendency to write symbols carelessly. Such instances as PB for Pb, MN for Mn, Co for CO, were quite common.

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Results : 1st Class, 229 ; 2nd Class, 989; Failed, 646 ; Total, 1,864. The number of papers in this stage which may be designated absolute failures appears to be smaller than it used to be, but, on the other hand, the papers that are distinctly good are very few. A striking feature is the large amount of inaccurate statement which may result from the mistaken effort on the part of many candidates to attack questions concerning the subject matter of which they have no real knowledge. The result is that many papers are received containing some good answers, together with some which seem to show a want of apprehension of principles, and a strange ignorance of facts. To tabulate the chief properties of chlorine, bromine, and iodine so as to show their relation to one another, and to indicate that they belong to the same family of elements, would appear to be a requirement which would be easily met by students even at this early stage, but though many tabular statements were put in there were few attempts to institute the comparison desired. Then, in regard to facts, great ignorance was displayed: for example, (Q. 21) one volume of CO was said to combine with one volume of oxygen ; (Q. 22) calcium carbonate was said to be decomposed by boiling in the water, and CaO precipitated ; (Q. 26) a common mistake was to represent Crso, or FeSo, as replacing the alkali sulphate in chrome and iron alums ; (Q. 24) the manufacture of bleaching powder was described, but the action of acids was almost always incorrectly represented. As nearly all candidates who attempted this question state that chlorine is liberated by the action of carbonic acid on bleaching powder, it may be as well to explain here that whatever constitution is attributed to bleaching powder, hypochlorous acid, and not chlorine, is the volatile product. This can be expressed by either of the following equations, which show that the chloride part of the molecule is unaffected by carbonic acid or carbon dioxide in the presence of water.

I. CaCl,Ca(CIO)2 + CO, + 11,0 = CaCl2 + CaCO3 + 211CIO
II. 2CaCl(CIO) + CO2 + 1,0 = CaCl, + CaCO3 + 2HCIO

The peculiar chlorinous smell of bleaching powder is due to hypochlorous acid liberated in this way. Chlorine is evolved only when a strong acid is used.

STAGE 3.
Results : 1st Class, 21 ; 2nd Class, 159 ; Failed, 218 ; Total, 397.
The papers were for the most part of poor quality. Two questions in
particular were answered in an unsatisfactory manner.
Q. 46. Explain carefully how the equivalent, atomic weight and

molecular weight of mercury or of zinc have been determined.
Q. 48. Define the term “acid.” In the light of your definition give

reasons for assigning or refusing the name “ acid ” to aqueous
solutions of the following :-Hydrogen sulphide, ordinary
sodium phosphate, sodium bi-sulphate, copper sulphate, ethyl

alcohol.
The doctrine of ions completely overshadows facts in the view of these
students, and seems to have been used by their teachers without sufficient
preparatory experimental or explanatory foundation.

Wild answers toother questions are quite common, such as “anhydrous hydrogen peroxide has been prepared by the direct combination of measured quantities of ozone and hydrogen,” or “ammonium amalgam is prepared by grinding ammonia and mercury together in a mortar." Very few knew anything about anhydrous hydrogen peroxide, the formulæ of the carbonyls were seldom given correctly, and the answers about barium carbonate and barium hydroxide were very bad.

Added to the lack of chemical knowledge, the misapplication of words and the grotesque spelling were in too many cases deplorable. The word " approximate" is commonly understood by these candidates to mean "inaccurate," as in the paper of 71530, who writes concerning the law of

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Dulong and Petit, that “though two (sic) approximate to afford a direct method for finding atomic weights," &c. Another frequently occurring expression is “solution of brine," meaning a solution of common salt.

Attention has been repeatedly drawn to the upsatisfactory answers in Section II. and the Examiners cannot but express their belief once more that the majority of the candidates who attempt these questions have done of that knowledge of manufacturing processes obtained at first hand or from the pages of the larger treatises which is prescribed by the syllabus.

HONOURS. Results : 1st Class, 1 ; 2nd Class, 7; Failed, 12 ; Total, 20. The most prominent defects in these papers on Theoretical Chemistry arise from imperfect knowledge of the current literature of the subject. Many answers were given to the question (62) about nitrogen trioxide, but none were satisfactory, and no candidate could show much knowledge of the application of electrolytic methods in Organic Chemistry (Q. 63). The chemistry of iodine compounds was also very imperfect in most cases, such compounds as the polyiodides, iodonium and iodoxy compounds being generally ignored, and even the iodates and periodates were imperfectly described. Out of 20 candidates, I was awarded First Class and 7 Second Class Honours.

INORGANIC CHEMISTRY, PRACTICAL,

STAGE 1. Results : 1st Class, 439 ; 2nd Class, 722; Failed, 306 ; Total, 1,467. The results are, on the whole, fair. The most unsatisfactory features of the work arise from lack of thought. In the first exercise the students were asked to apply heat to a powder in a dry test tube and record the effects observed. The powder consisted of a mixture either of mercuric iodide and zinc oxide or of mercuric iodide and cuprous iodide. Instead of following instructions many of the candidates proceeded to apply litmus, lime water, etc., and then to write out a formal table on the "experiment, observation inference" plan, wholly ignoring the facts to be observed. The training of the intelligence, which should be the highest aim of teaching, is not yet the definite and paramount aim of many science teachers. The same defect is also apparent in the answers to the other two exercises. A large number of candidates fail to distinguish between "loss of weight" and“ residue,” thus giving wrong results of experiments otherwise correctly done. If this mistake arises, as is possible, from misunderstanding of the word “residue,” it ought to be put right by the teachers. This is by no means the first time that this kind of error has been noticed.

STAGE 2. Results : 1st Class, 556 ; 2nd Class, 636; Failed, 444 ; Total, 1,636. The general impression derived from a perusal of these papers is, as in previous years, the superiority of the quantitative over the qualitative work. A feature to be regretted is the number of cases in which things not present are found in the substances supplied for qualitative analysis. This generally arises from imperfect separations, e.g., when lead is present the candidates also find aluminium. There is also, in certain schools, a tendency to make “ shots.”, at supposed constituents of the mixtures by means of individual tests without attempting separations, and the condition of valency in which iron, for example, occurs is very rarely ascertained. There is no excuse for slipshod work of this kind if the students have had only a reasonable amount of practice, as the use of books is allowed during the examination. It would almost appear from the results sent in by some candidates that they have used the book for the first time in the examination room. In the theoretical paper the customary ignorance of the explanation of analytical processes and reactions was displayed. It would appear that very little teaching is given in this direction.

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