SECTION III.- ORGANIC COMPOUNDS.

INTRODUCTORY SUBJECTS.

1082. How are organic distinguished from inorganic bodies ? Give the various definitions of organic chemistry which have been proposed.

1083. Name the elements most commonly found in organic bodies. Which element is present in all organic bodies ?

1084. The compounds of carbon are more numerous than those of all the other elements.

How do you account for this ?

1085. Explain the terms substitution, saturated, nonsaturated, organic radical, homologue, and hydrocarbon. Illustrate your meaning by examples.

1086. Give examples of organic and inorganic compound radicals. Give an example of an inorganic homologous series.

1087. How would you examine a substance so as to ascertain whether it is organic or inorganic ?

1088. How could you detect the presence of carbon, hydrogen, and oxygen in sugar ?

1089. How are chlorine, iodine, sulphur, and nitrogen detected in organic bodies ? 1090. Describe

fully the process employed for the quantitive analysis of an organic body containing carbon, hydrogen, and oxygen. Sketch the apparatus.

1091. Give two methods for determining the amount of nitrogen present in an organic body.

1092. How is the quantity (a) of chlorine; (6) of sulphur determined in an organic compound?

1093. Describe Frankland's process for the determination of boron in organic bodies.

1094. How much carbon is contained in each of the following weights of carbon dioxide : (a) 1'2769 gramme, (6) 0:8793 gramme, (c) 0:9876 gramme? How much hydrogen is contained in each of the following weights of water : (a) 247637 grammes, (6) 0'2987 gramme, (c) 097896 gramme?

1095. If 4'3679 grammes of alcohol (C2H60) were

completely burned, what weight of carbon dioxide and of water should be produced ?

1096. Calculate the percentage composition and formulæ of the organic compounds which yielded the following analytical results :

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(a). Substance taken

0°757 gramme.
Carbon dioxide obtained 0:889
Water obtained

0.267
(6). Substance taken

0'3989 Carbon dioxide obtained 0·7978 Water obtained

Oʻ3329 (c). Substance taken.

o'9002 Carbon dioxide obtained = 1°7217 Water obtained

1'0564
(d). Substance taken

O‘3665
Carbon dioxide obtained

0'7331
Water obtained

Oʻ1521
(e). Substance taken = 04639

Carbon dioxide obtained 0:6377
Water obtained

05217

2

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1097. 1'2435 gramme of an organic body having the general formula C H2n is submitted to analysis. Find

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the weights of carbon dioxide and water which should be obtained.

1098. Find the percentage composition and formula of a substance from the following analytical results :(a). Substance taken

— O‘2491 gramme.
Carbon dioxide obtained Oʻ1829
Water obtained

= 0'1492

also (6). oʻ2381 gramme of the substance yielded 0.4276

gramme ammonium chloride. 1099. A substance containing carbon, hydrogen and nitrogen, gave the following analytical results :-(a). Substance taken

0'4124 gramme.
Carbon dioxide obtained 0-9885
Water obtained

0'3491

also (6). oʻ1123 gramme of the substance yielded 0·8021

gramme double chloride of platinum and ammonium. Find the percentage composition and formula of the substance.

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1100. O‘2379 gramme of strychnine (C2H22N2O2) is analysed. Find the weights of carbon dioxide and water which should be obtained, and the volume of nitrogen measured at 10° C. and 757 m.m. pressure.