{"id":20,"date":"2014-10-21T09:39:20","date_gmt":"2014-10-21T09:39:20","guid":{"rendered":"http:\/\/blogs.glowscotland.org.uk\/gc\/hyndsechchemu3hwrk\/chromatography\/"},"modified":"2014-10-21T09:51:34","modified_gmt":"2014-10-21T09:51:34","slug":"chromatography","status":"publish","type":"page","link":"https:\/\/blogs.glowscotland.org.uk\/gc\/hyndsechchemu3hwrk\/chromatography\/","title":{"rendered":"Chromatography"},"content":{"rendered":"

1.<\/strong>\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 Use the diagram showing a paper chromatography experiment to define the following terms:<\/p>\n

\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 (a) mobile phase<\/p>\n

\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 (b) stationary phase<\/p>\n

\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 (c) Rf value<\/p>\n

2.<\/strong>\u00a0\u00a0 Compare and explain the speed at which the following move up the paper in paper \u00a0\u00a0\u00a0\u00a0 chromatography.<\/p>\n

\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 (a) Large molecules compared with small molecules.<\/p>\n

\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 (b) A polar solvent compared with a non-polar solvent.<\/p>\n

\u00a0<\/strong><\/p>\n

3.\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 <\/strong>An organic chemist is attempting to synthesise a fragrance compound by the following chemical reaction.<\/p>\n

\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 compound <\/em>X <\/em>+ <\/em>compound <\/em>Y <\/em>\u2192<\/em> <\/em>fragrance compound<\/em><\/p>\n

After one hour, a sample is removed and compared with pure samples of compounds X and Y using thin-layer chromatography. Which of the following chromatograms shows that the reaction has produced a pure sample of \u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 the fragrance compound?<\/p>\n

4.<\/strong>\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 Describe how chromatography can be used to identify the amino acids that make up a protein.<\/p>\n

5.<\/strong>\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 Label the parts A \u2013 F on the gas chromatography equipment below:<\/p>\n

Labels<\/span><\/p>\n

sample inlet<\/p>\n

oven<\/p>\n

gas (mobile phase)<\/p>\n

detector<\/p>\n

coil<\/p>\n

chromatogram<\/p>\n

6.<\/strong>\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 In terms of gas liquid chromatography<\/p>\n

\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 (a) what is the mobile phase?<\/p>\n

\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 (b) what is the stationary phase?<\/p>\n

\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 (c) why is the injection port heated?<\/p>\n

\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 (d) explain what is meant by retention time.<\/p>\n

7.\u00a0\u00a0 <\/strong>\u00a0\u00a0\u00a0\u00a0 Give 3 different uses of gas liquid chromatography.<\/p>\n

8.\u00a0\u00a0 <\/strong>\u00a0\u00a0\u00a0\u00a0 (a) Which gases are usually used as carrier gases in gas chromatography?\u00a0<\/p>\n

\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 (b) Explain why these particular gases are used.<\/p>\n

9.<\/strong>\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 If the stationary phase in gas chromatography is non-polar, how would the retention times of polar and non-polar samples in the column compare to each other?<\/p>\n

10.<\/strong>\u00a0\u00a0\u00a0\u00a0\u00a0 A technician analyses a mixture of hydrocarbons using gas chromatography. She first calibrates the equipment using standard hydrocarbons. The retention times of these hydrocarbons are shown in the table.<\/p>\n\n\n\n\n\n\n\n\n
hydrocarbon<\/td>\nformula<\/td>\nretention time in minutes<\/td>\n<\/tr>\n
methane<\/td>\nCH4<\/sub><\/td>\n1.7<\/td>\n<\/tr>\n
ethane<\/td>\nC2<\/sub>H6<\/sub><\/td>\n2.2<\/td>\n<\/tr>\n
propane<\/td>\nC3<\/sub>H8<\/sub><\/td>\n3.5<\/td>\n<\/tr>\n
butane<\/td>\nC4<\/sub>H10<\/sub><\/td>\n4.0<\/td>\n<\/tr>\n
pentane<\/td>\nC5<\/sub>H12<\/sub><\/td>\n7.4<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0<\/p>\n

The technician then analyses the mixture of hydrocarbons. The recorder print out from this analysis is shown below.<\/p>\n

(a) How does the recorder print out show that butane has the highest concentration?<\/p>\n

(b) Use data in the table to draw a conclusion relating the formula of each hydrocarbon to its retention time.<\/p>\n","protected":false},"excerpt":{"rendered":"

1.\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 Use the diagram showing a paper chromatography experiment to define the following terms: \u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 (a) mobile phase \u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 (b) stationary phase \u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 (c) Rf value 2.\u00a0\u00a0 Compare and explain the speed at which the following move up the paper in paper \u00a0\u00a0\u00a0\u00a0 chromatography. \u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 (a) Large molecules compared with small molecules. \u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 (b) A … Continue reading “Chromatography”<\/span><\/a><\/p>\n","protected":false},"author":2454,"featured_media":0,"parent":0,"menu_order":0,"comment_status":"open","ping_status":"open","template":"","meta":{"footnotes":""},"class_list":["post-20","page","type-page","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/blogs.glowscotland.org.uk\/gc\/hyndsechchemu3hwrk\/wp-json\/wp\/v2\/pages\/20","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/blogs.glowscotland.org.uk\/gc\/hyndsechchemu3hwrk\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/blogs.glowscotland.org.uk\/gc\/hyndsechchemu3hwrk\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/blogs.glowscotland.org.uk\/gc\/hyndsechchemu3hwrk\/wp-json\/wp\/v2\/users\/2454"}],"replies":[{"embeddable":true,"href":"https:\/\/blogs.glowscotland.org.uk\/gc\/hyndsechchemu3hwrk\/wp-json\/wp\/v2\/comments?post=20"}],"version-history":[{"count":1,"href":"https:\/\/blogs.glowscotland.org.uk\/gc\/hyndsechchemu3hwrk\/wp-json\/wp\/v2\/pages\/20\/revisions"}],"predecessor-version":[{"id":49,"href":"https:\/\/blogs.glowscotland.org.uk\/gc\/hyndsechchemu3hwrk\/wp-json\/wp\/v2\/pages\/20\/revisions\/49"}],"wp:attachment":[{"href":"https:\/\/blogs.glowscotland.org.uk\/gc\/hyndsechchemu3hwrk\/wp-json\/wp\/v2\/media?parent=20"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}