The retention time for cyclohexane on a gas chromatography instrument is 0.75 minutes. the temperature of the gas chromatography column is 70 degrees c and the gas flow rate is 60 ml/minute.

(a) would the retention time be higher or lower if the column temperature is raised to 100 degrees c?
(b) would the retention time be higher or lower if the flow rate is changed to 30 ml/minute?
(c) would the retention time be higher or lower if the column length was decreased to 1/2 the length?

(a) Lower

(b) Higher

(c) Higher

Explanation:

Gas chromatography is a common type of chromatography used in chemistry for separating and analyzing compounds that can be vaporized without decomposition. The interaction of chemicals with the stationary phase cause different retention times in different compounds.

(a) Would the retention time be higher or lower if the column temperature is raised to 100 degrees C?  The  raising of column temperature will produce an increasing in vaporization of cyclohexane doing retention time lower.

(b) Would the retention time be higher or lower if the flow rate is changed to 30 mL/minute?  A decreasing in the flow rate will produce the rate of the cyclohexane decrease doing retention time higher.

(c) Would the retention time be higher or lower if the column length was decreased to 1/2 the length? If column lenght was decreased the cyclohexane must travel less distance doing retention time higher.

I hope it helps!

i just calculated it all out, and not including weekends, and all the different days off. as of this school year (2018-2019) students are spending 2198 hours in school this year

answer is: naturally occurring solid, inorganic compound or element is mineral.

minerals usually have crystalline form, that means than crystal constituents (atoms, molecules or ions) are arranged in a highly ordered microscopic structure, forming a crystal lattice that extends in all directions.

for example magnetite is a mineral of iron oxide (fe₂o₃).

calcite is a carbonate mineral and the most stable polymorph of calcium carbonate (caco₃).

dolomite is an   carbonate mineral composed of calcium magnesium carbonate (camg(co₃)₂).