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1132. How does marsh-gas occur in nature ? By what other names is the substance known ? Give four distinct methods for its preparation.
1133. What are the products of the action of chlorine on marsh-gas?
1134. Nine litres of marsh-gas are mixed with nine of chlorine and exposed to light. Give the volumes and weights of the products.
1135. What weight of sodium acetate when heated with caustic soda is needed to yield 275 c.c. of marsh-gas at N.T.P. ?
1136. One hundred and eighty-nine c.c. of marsh-gas are completely burned in air. Find the volume of air required and of the products of combustion at N.T.P.
1137. What volume of oxygen must be exploded with 150 c.c. of marsh-gas so as to ensure complete combustion ?
1138. What volume of marsh-gas at N.T.P. when passed over heated copper oxide should yield 10 grammes of carbon dioxide ?
1139. Give two methods for the preparation of methyl chloride. What is the action of potash on it?
1140. How is chloroform prepared on the large scale ? What is the action of nascent hydrogen, and of chlorine
on it ?
1141. What products are obtained by the destructive distillation of wood, and how is the wood spirit separated from them, and obtained pure ?
1142. How is methyl alcohol obtained from (a) methyl chloride, (6) gaultheria oil ? What is the action of potassium on methyl alcohol ?
1143. What volume of oxygen is required for the complete combustion of 7 grammes of methyl alcohol?
1144. What two compounds have the empirical formula C2H3N ? How is each prepared, and what is the constitutional formula for each ? From which, and how, could an ethyl compound be obtained ?
1145. Give several reactions for preparing ethyl hydride. How has it been proved identical with dimethyl ?
1146. What is the action of chlorine on ethyl hydride?
1147. How is ethyl chloride prepared (a) by Grove's method, (b) by other methods ? What is the action of potash on it?
1148. How is ethyl iodide prepared ? What weight of it contains 7.89 grammes of iodine ?
1149. How is ethyl alcohol obtained from grape sugar ? What other products are simultaneously produced ?
1150. What is absolute alcohol, and how is it prepared ?
1151. How is the amount of alcohol in a mixture of alcohol and water accurately ascertained ?
1152. What is the action on alcohol of each of the following bodies ? (a) sodium, () chlorine, (c) sulphuric acid, (d) a mixture of sulphuric acid and potassium bichromate. Give equations for the reactions.
1153. Give the formulæ of several analogous ethyl and potassium compounds.
1154. What occurs when alcohol vapour is passed through a red-hot tube ?
1155. How did Berthelot obtain alcohol from inorganic materials ? Give other methods.
1156. Seventeen grammes of alcohol are burned completely. Find the volume of carbon dioxide obtained at N.T.P., and also the weight of water produced.
1157. Find the volume of air at N.T.P. required for the complete combustion of 19 c.c. of absolute alcohol at 0° C. (S. G. at o° C. 0.80625). Find also the volumes of the gaseous products.
1158. By the action of potassium on alcohol 1987 c.c. of hydrogen at N.T.P. were obtained. Find the weight of alcohol decomposed and of potassium used.
1159. What is the composition of the substance called propiontrile ? How is it prepared, and how would you prepare the body with which it is isomeric ?
1160. What is mercaptan, and how is it prepared ?
1161. Give several methods for the preparation of ethylene. Represent the reactions by equations.
1162. What is the volume at N.T.P. of 7.89 grammes of ethylene, and what volume of oxygen is required to burn it ?
1163. Starting with carbon and hydrogen how may ethylene be prepared ?
1164. What occurs when a mixture of ethylene with twice its volume of chlorine is kindled ?
1165. How may ethylene be made to combine with chlorine? Give the properties of the compound produced, and sketch the apparatus you would employ to prepare it.
1166. Explain the difference in constitution between ethylene and its isomer ethylidene.
1167. What is glycol ? State fully how it is prepared, and what occurs when it is oxidized. Give equations.
1168. What is the action (a) of potassium, (6) of phosphorus pentachloride, (c) of hydrochloric acid, on glycol ?