George S Newth.

A text-book of inorganic chemistry online

. (page 62 of 67)
Online LibraryGeorge S NewthA text-book of inorganic chemistry → online text (page 62 of 67)
Font size
QR-code for this ebook

Transpiration of gases, 85
Triad elements, 59
Triclinic system, 162
Tridymite, 633
Triethylamine, 150
Triethyl silico-formate, 631
Trivalent elements, 59
Trona, 540

Truncated crystals, 162
Tungstates, 664
Tungsten, 664

,, chlorides, 665
,, oxides, 664
Turn bull's blue, 680
Turpeth mineral, 434

Turquoise, 614
Type metal, 492
Typical elements, 115
Twin crystals, 634


Unit of heat, 165, 326

,, volume, 44
Unsaturated compounds, 62
Uranates, 664
Uraninite, 267
Uranium, 664

,, chlorides, 665

oxides, 664
Uranous salts, 665

,, sulphate, 665
Uranyl salts, 665
Urea, 13, 24, 295

Vanadates, 655
Vanadite, 655
Vanadium, 655

,, chlorides of, 656

,, oxides of, 655

,, oxychlorides of , 656
Vaporisation, latent heat of, 130
Vapour densities of elements, 42

pressures of solutions: 133
Vapour tension, 128
Verdigris, 557
Vermilion, 604
Vinasse, 521

,, cinder, 521
Vital force, 295
Vitriol chambers, 430
Volatile alkali, 506

WATER, 203

,, Clark's process for softening,


,, colour of, 212
,, compressibility of, 213
, , electrolysis of, 207
,, freezing of, 131
,, gas, 297
,, gravimetric composition of,


,, hardness of, 221
maximum density of, 214



Water of constitution, 218

of crystallisation, 216
rain, 220

,, solubility of gases in, 147
,, ii i salts in, 150

,, solvent power of, 216
,, supercooling of, 136
,, volumetric composition of,


Waters, chalybeate, 220
,, dangerous, 223
,, deep well, 220
,, fresh, 220
,, hard, 221

mineral, 219
,, natural, 218
potable, 223
,,. river, 220
safe, 223
,, sea, 219
,, spring, 219
,, suspicious, 223
Wavellite, 452
Wei don's process, 357
Welsbach burner, 339
White arsenic, 485
,, cast iron, 674
,, lead, 651

metal (copper), 551
nickel, 687
,, vitriol, 218
Witherite, 586
Wohlerite, 627
Wolfram, 664
,, ochre, 664

Wood's fusible metal, 500
Wrought iron, 675
Wulfenite, 664
Wurtzite, 595

Xenon, 269

Ytterbium, 606
Yttrium, 606



alloys of, 593

,, aluminate, 591

,, amalgam, 601

,, blende, 591

,, carbonate, 596

,, chloride, 594

,, chromite, 662

,, granulated, 174

,, hydroxide, 594
methyl, 313

,, nitrate, 240
oxide, 593

,, spar, 591

,, spinnelle, 591

,, sulphate, 595
sulphide, 595

,, white, 594
7.inci carbonas, 596
Zinc-copper couple, 173, 313
Zircon, 627
Zirconium, 627

Edinburgh & London






1. Define chemistry.

2. To what other subject is chemistry closely related? What of the
line of demarcation between them?

3. Classify the changes which matter may undergo.

4. To what class should the change taking place in the melting of
ice be assigned; the slaking of lime; the magnetization of steel;
the solidifying of egg albumen under heat; the souring of milk?
Give reason for classification selected?

5. Do physical changes always attend chemical changes and vice
versa? Illustrate.

6. Define chemical change, and physical change from a practical,
and from a theoretical standpoint.

7. Is the conversion of oxygen into ozone, or of ammonium cyanate
into urea, chemical in nature?

8. What is the modern view of the constitution of matter? Is this a
theory or a truth?

9. Define molecule. Substitute "mass" for "weight" in the defini-
tion given and comment upon the change.

10. What concrete illustration of the size of a molecule suggested by
Lord Kelvin?

11. What seems to be the maximum limit of the size of the molecule?

12. Basing an estimation on the maximum diameter of a molecule,
how many would it take, placed side by side, to reach through
one leaf of the text-book?

13. What force operates to hold molecules in masses? Is this a chemical
or physical force?

14. Are molecules without motion in solids? Distinguish between a
solid, liquid and gas based upon molecular relationship.

[Copyright, 1912, by Longmans, Green & Co.]

Questions on Chemistry

15. What seems necessary to convert a solid into a gas and vice versa?

16. Discuss the complexity of the molecule.

17. What is the force called which holds together the units of the

1 8. Compare the molecule of sugar to the solar system.

19. Define atom. Is the atom real or imaginary?

20. Discuss the difference between physical and chemical change,
using water as an example.

21. What is the significance of the word atom? Was the word applicable
in Avogadro's time? What objection might Lord Kelvin have made
to this choice? Or in other words, is the term as applicable to-day
as when it was chosen?

22. Does the theory of electrons disturb the fundamental doctrines
of chemistry?


1. Define an element from the experimental standpoint. Also define
a compound from the experimental standpoint.

2. Define element, and compound, from a theoretical standpoint.

3. How many elements are known at present? Give evidences support-
ing the belief that this number will be augmented. Is it possible

that the number will be reduced? Explain how this might occur.

4. Discuss definiteness of the number of elements. Is the number
of compounds fixed? Discuss the limits of compounds.

5. Discuss the statement that certain elements might be blotted out
of existence without their absence being appreciated.

6. The average chemist needs a working knowledge of about how many

7. Into what classes may the elements be divided? Define each class.
What of the boundary line between these classes?

8. Discuss the constitution of the elementary molecule. In what
proportion of cases is there definite knowledge of the number of
atoms in the elementary molecule?

9. Give examples of mono-, di-, tri-, and tetra-atomic molecules.
Is NaOH to be considered a tri-atomic molecule?

10. Define a mixture from an experimental viewpoint. From a hypo-
thetical viewpoint.

11. If two or more substances are brought together, what results may
follow? How determine which occurred?

12. How do the properties of a given compound compare with the
properties of the elements producing it? Elucidate.

13. What is meant by a stable element or compound? Is there any
basis of determining the probable stability of a combination with-
out experimentation, e.g., by inspection?


Questions on Chemistry

14. What is meant by chemical affinity? What is the nature of chemical

15. Define chemical action or chemical change.

1 6. What forces act favorably to chemical action? Give an illustration
in each case.

17. Define catalysis. Discuss several possible definitions.

1 8. Classify chemical changes. Give several equations representing
the change in each class.

19. Distinguish between analysis and synthesis. Give an equation
representing an analytic change; a synthetic change.

20. Classify those chemical changes expressed by the following:

2KC1O 3 heated = 2KC1+3O 2 ;

NH 4 OH heated = H 2 O+NH 3 ;

Mn0 2 +2NaCl +2H 2 SO 4 = MnSO 4 +Na 2 SO 4 -f-2H 2 O+Cl 2 ;

CaCO 3 heated =CaO+CO 2 .

21. Classify the chemical reaction expressed by the following equation:

3C 2 H 2 =C 6 H6.

22. "Gaseous hydrofluoric acid rapidly attacks glass." Criticise
the above expression and state it in harmony with the criticism


1. What method of procedure was followed in naming the elements?
Suggestion: Make a complete list of the elements together with
the derivation of each, drawing upon any authoritative source.

2. What application is made of the "um" terminal in naming new
elements? Does this apply in naming elements early discovered?

3. Is selenium or selenion the more applicable nomenclature?

4. What is a binary compound? Are ZnO, HgS, NaCl, and AgBr
examples? Are ZnCl 2 , Al 2 Os, Fe 3 O 4 , and CioHie examples?

5. What general rule is applied in the nomenclature of binary com-
binations? Illustrate. Apply this rule to CH 4) C 2 H 2 , HN 3 and HC1.

6. In case two elements unite in more than one ratio, how is the
binary rule applied? Illustrate using CaO and CaO 2 ; CuO and
Cu 2 O; HgCl and HgCl 2 ; FeCl 2 and FeCl 3 ; SbCl 3 and SbCl 5 .

7. What name is applied to each of the following: NaOH, A1(OH) 3 ,
NH 4 C1, NH 4 Br, NH 4 OH, KCN, and COC1 2 ? Do these belong to
the binary class of combinations?

8. Discuss the significance of the prefixes sub, proto, per, and hyper.

9. Define oxide, and classify the oxides with respect to their behavior
toward water.


Questions on Chemistry

10. What class of elements do you find characteristic of each different
class of oxides?

11. What element entering into all acids? What element entering
almost all acids? How are these latter acids named?

12. What is meant by the basicity of an acid? Give an illustration of
a mono-, di-, and tri-basic acid.

13. What is a thio acid? How are these acids named? Give examples
using names and formulae.

14. Discuss the meaning of the term base. Define a hydroxide.

15. What is a salt? Classify the salts, and define each class.

1 6. To what class of salts does each of the following belong: Na2SO4,
ZnSO 4 , NaHCO 3 , NaC 2 H 3 O 2 , NaKSO 4 , SbOCl, NaH 2 PO 4 , NaHSO 3 ,
NaH 2 PO 2 , NaOCl, and ZnCO 3 .2Zn(OH) 2 ?

17. Is an acid salt acid to litmus? Is a normal salt neutral to litmus?

1 8. Does hydrogen form salts? If so, are these salts acid, neutral or
alkaline toward litmus?

19. Give the scheme of nomenclature as applied to salt combinations.
Show how this applies to the salt derivative of different acids that
may be mentioned.


1. What governs the selection of a symbol for an element?

2. Is the use of a symbol or of a formula in a sentence to avoid using
the full name of the element or compound allowable?

3. For what does the symbol H, or Cl, etc., really stand?

4. Read the list of elements through pronouncing the name of each
element clearly and correctly noting the symbol for each.

5. List those elements whose symbol is not derived from the common
name of the element.

6. What is the significance of the italics used in the table of elements?

7. Define formula and give half dozen examples. Distinguish between
symbol and formula.

8. Classify the following with respect to symbol, formula.etc. : NaCl,
O, O 2 , O 3 , P, PH 3 , P 4 , A, Zn, CaSO 4 .2H 2 0.

9. What is the significance of the subscript and of the coefficient used
in representing various substances? Do H 2 and 2H represent a
difference in substance, quantity, or condition?

10. Distinguish between a simple radical and a compound radical.

11. Criticise the following: "The reaction NH 3 -f-HCl = NH 4 Cl takes
place on simple contact of the two gases," and "Balance the equa-
tion Na 2 CO 3 +HCl = NaCl+H20+CO 2 ."

12. What fundamental law is exemplified in every chemical equation?


Questions on Chemistry

13. Interpret the following expressions or formulae: NH 4 NOs,
NaNH 4 HPO 4 , CaSO 4 . 2H 2 O, 2CaSO 4 . H 2 O, 3 Cu(AsO 2 ) 2 . Cu(C 2 H 3 O 2 ) 2 .
What number of atoms of each element is represented in the last

14. Discuss the significance of the plus sign as employed in a chemical


1. What is the atomic theory? By whom was it formulated and when?
Was this theory original with the scientist named?

2. What laws were evolved from a quantitative study of chemical com-
pounds? Are these gravimetric or volumetric in character? Dis-
cuss their importance to chemistry as a science?

3. After the law of conservation of mass, what is the most fundamental
law of chemistry?

4. Who first called attention to the constancy of composition of com-
pounds, and when? Prior to this time, what was the belief?

5. In case two reacting substances are present in quantity other than
that normally found in their product, what is the result? Give an

6. Show why all processes of quantitative analysis hinge upon the
truth or falsity of the law of definite or constant proportion.

7. State the law of multiple proportion and mention its discoverer.

8. Apply the direct statement of the law of multiple proportion to
the actual weight relationship of the oxides of nitrogen, showing
clearly what the law means.

9. Iron pyrite is 46.62 per cent iron and 53.38 per cent sulphur, while
precipitated iron sulphide is 63.59 P er cen t and 36.41 per cent.
Apply the law of multiple proportion.

10. Are the ratios obtained from accurate analytical results approx-
imately whole numbers or are they exactly whole numbers?

11. State the law of equivalent proportion. Restate it in different

12. Using the compounds phosphorus trichloride, and phosphine, show
the application of the law of reciprocals.

13. Using carbon dioxide, carbon disulphide, and sulphur dioxide, show
another feature of the law of reciprocals.

14. What determines whether the equivalents shall be in multiple ratio
or not? Illustrate by using water, carbon dioxide and marsh gas.
Water, carbon monoxide and ethylene. Water, carbon dioxide
and acetylene. Water, carbon monoxide and acetylene.

15. Show that the ratio in which hydrogen, sodium, potassium, silver,
and mercury unite with one part of chlorine is preserved in their
union with one part of bromine, or with one part of oxygen.

16. What is the equivalent weight of any element?


Questions on Chemistry

17. What was Dalton's belief regarding the relation of equivalent
weights and atomic weights?

1 8. Show that Dalton's theory satisfies the law of definite proportion;
of multiple proportion; of reciprocal proportion.

19. State the law of Gay-Lussac. In applying this law, is it necessary
that all factors and products be gaseous? Does the law apply to
liquids or solids?


1. What deduction did Dalton make concerning the weight of the
atoms as compared with the equivalent weights?

2. What formula did Dalton give to marsh gas, and to ethylene?
Upon what assumption were these formulae given?

3. After obtaining weight relationship of the elements of a compound,
is a knowledge of the number of atoms in a molecule essential to
the development of its formula? Give an illustration.

4. What important methods are followed in determining atomic weights?

5. Prove that water is not HO 1 :8.

6. What reason may be given for changing Dalton's atomic weight
of carbon to the present one?

7. Define atomic weight.

8. Are atomic weight values related to weight expressed in metric
or in avoirdupois systems? Explain.

9. The atomic weight of what element is taken as the standard of
comparison of all atomic weights? State reasons for this selection.

10. Account for frequent contradictions in atomic weight tables.

11. State the law of Gay-Lussac and give half a dozen illustrations
not mentioned in the text.

12. Just how is volumetric relationship made a means of determining
atomic weight?

13. Who first explained the proportionate relationship between weight
and volume of gases, and when?

14. Reverse Avogadro's law. Restate it, considering the number of
molecules as varying.

15. In stating the density of gases, what is taken as the standard?

16. What other term is frequently used instead of density? In case
the substance in gaseous state is normally a liquid or solid, what
term is commonly used?

17. How is the number of atoms in a molecule of hydrogen established?
Does this also establish molecular formula for any other substances?

18. What relation exists between density of a substance in gaseous
state and its molecular weight, and vice versa?

19. Suppose the density be stated on an air basis, how then determine
the molecular weight?


Questions on Chemistry

20. Write the molecular symbol for all the elementary substances pos-

21. Show how an application of Avogadro's law will establish the
atomic weight of oxygen. Of nitrogen. Of chlorine.

22. Show how the densitv of an element in gaseous state may be one-
half of, identical with, or twice as great as, the atomic weight.

23. Define a unit volume. What volume does the molecule occupy?

24. Define atomic weight from the standpoint of volume occupied.
Show this definition to be faulty.

25. Is the volumetric method of determining molecular weights, taken
by itself, altogether dependable? Amplify.

26. Define specific heat.

27. What is chosen as the unit for heat comparisons, and why?

28. How proceed to determine the specific heat of a substance?

29. What relation exists between the specific heat of an element in
the solid state and its atomic weight? Who discovered this law, and

30. Carefully state the law relating to specific heat. Define the term
thermal capacity as used in the law comparing this use with that
in the preceding discussion in the text. Restate the law in another

31. What is atomic heat? What number is commonly called the atomic
heat constant? Is it really a constant? Elucidate.

32. Name substances giving abnormal atomic heat values. How are
they made to approximate the constant?

33. If the "constant" is not a constant but an approximation, how can
it be of use in the determination of those highly accurate values
known as atomic weights?

34. Show the application of specific heat data to the fixing of the weight
of thallium. Of indium.

35. What can be said of the atomic heat of an element in combination?

36. What is necessary to know in order to calculate the molecular
heat of any compound? Show this with cuprous and cupric oxides.

37. How does the molecular heat of silver chloride and of sodium chloride
compare? Compare their specific heats. Elucidate.

38. How determine the specific heat of oxygen?

39. Show how molecular heat can be of service in determining the
valency of an element.

40. What value should be attached to a calculation of an atomic weight
of arsenic based upon a determination of the specific heat of as com-
plex a compound as Paris green?

41. What is the law of isomorphism? Who announced it, and when?

42. What is meant by isomorphous substances and what test is applied to
determine if this condition exists between two or more compounds?

43. Define isogonism.


Questions on Chemitsry

44. Upon what assumption rests the application of Mitscherlich's law?

45. State how the ammonium radical seems to function in its various
crystalline compounds.

46. What use was made of the law of isomorphism by an eminent chemist ?


1. In what sense is a chemical equation purely a mathematical expres-

2. Given the formula of a compound, how determine its formula
weight? What is the unit upon which this weight is based?

3. Under what conditions will a chemical equation express both
weight and volume relationship?

4. What advantages in calculation are derived from the use of a molec-
ular expression rather than an atomic expression?

5. Demonstrate the above, using combinations of hydrogen, mercury,
and phosphorus, with the element chlorine.

6. In making a calculation involving volume, from a chemical equa-
tion, is it essential that all substances entering into the equation
be gases? Is it essential that all substances directly involved in
the given problem be gases?

7. What is the weight of a litre of hydrogen gas? Does the answer
given admit of discussion?

8. What is a crith? State the weight of any gas in terms of criths.
Is this applicable equally to elements and compounds?

9. What is a gram-molecule?

10. What weight of any substance, either elementary or compound, is
found occupying two unit volumes?

11. What general weight relationship exists between like volumes of
different substances in gaseous state?

12. What volume in litres is occupied by I gram of hydrogen? By 16
grams of oxygen? By 35.5 grams of chlorine? By 4 grams of helium?

13. Is the volume of any element which is occupied by its atomic
weight expressed in grams a constant? Explain.

14. What is the gram-molecular volume of a substance? Is this value
equally true of element or compound? Of liquid or solid while in
gaseous state?

15. SOD grams of marble will produce how many litres of carbon dioxide?

1 6. Determine the exact atomic weight of potassium, chlorine and
silver from the following data: 10 grams of potassium chlorate
developed a constant weight of 6.079 grams when highly heated.
2 grams of this residue dissolved and precipitated with silver nitrate
give 3.845 grams of dry silver chloride. 2.657 grams of a compound
exactly similar to this precipitate are made by heating 2 grams of
silver in a stream of chlorine.


Questions on Chemistry


1. Define valency. Is valency measurable?

2. What is meant by a monad? A triad? A pentad?

3. In general, how is the valency of an element determined?

4. When the valency which any element exercises toward some typical
element is determined, will this be found to be the valence com-
monly exercised toward other elements?

5. What seems to be the limit of valence toward the element hydrogen?

6. What general rule is followed in fixing the valence of any given

7. What means are commonly employed to express the valence exercised
by the various elements of a compound? (Note: This is commonly
called graphic formula.)

8. Into what error may a stationary, two-dimensional representation
of a molecule lead the student?

9. Show that the term affinity as used in connection with valence has
no reference to chemical affinity or chemism.

10. What is meant by a saturated and an unsaturated compound?

11. Is the number of divalent atoms held in combination with another
atom a measure of its valence? Explain.

12. What valence does carbon exercise in each of its two common
oxides? Do methane and carbon tetrachloride assist in determining
this valence?

13. Give a graphic representation of the sulphur dioxide and sulphur
tri oxide molecules. Are these formulae known to be correct?
Upon what is a belief in their correctness based?

14. Discuss causes influencing an element to exercise different valencies.

15. Are we justified in supposing an increase ot valence when unsaturated
molecules take on other groups?

1 6. Give examples of more complex combinations in which none of
the elements are believed to increase their valency.

17. Is the so-called water of crystallization held in chemical union with
the salt molecule in the crystalline product?

18. Explain valence relations in hydrous crystals, double salts, basic
salts and similar molecular combinations.

19. What is meant by a residual combining capacity of an atom?

20. What is the modern conception of valency?


1. Does the volume of every substance respond to thermal changes?
Is any degree of constancy observed?

2. State the law of Charles. Is this statement either absolutely or
practically true?


Questions on Chemistry

3. Compare the coefficient of expansion of air with that of several
other gases. What class of gases show greatest deviation from
air? What is meant by coefficient of expansion?

4. How can any fixed coefficient be established for a volume that'
is as varying as the temperature?

5. What is the accepted coefficient of expansion of gases? Express
its value in common fraction form.

6. What is the standard temperature? What is meant by absolute

7. If temperature be given in centigrade degrees how convert to abso-
lute degrees?

8. With the temperature changes stated in absolute degrees, how may
the law of Charles be stated?

9. Letting T and V equal the initial and t and v the new temperatures
and volumes respectively, show that T: t::V: v.

10. State Boyle's law. When was this relation between pressure and
volume recognized? What is the standard pressure?

11. Is Boyle's law a statement of fact? Discuss deviations. Is it
practically true?

12. Let P and V represent initial and p and v new pressures and volumes
respectively, state Boyle's law in a formula.

13. Apply the formula .' V : : V: v in solving the following: 100 litres

of gas measured under laboratory conditions of 21 C. and 745
mm. pressure, represent what volume under standard conditions ?

14. Rearrange the formula previously used in such a way as to apply
if the temperature and pressure changes are to affect weight relations
instead of volume relations.

15. Describe an experiment designed to show the behavior of sulphur
dioxide when cooled, and when compressed.

1 6. What gas was first liquefied, when, and by whom?

17. What early experimenter gave us definite knowledge regarding
liquefaction of gases? Describe his methods.

Online LibraryGeorge S NewthA text-book of inorganic chemistry → online text (page 62 of 67)