Phase Chemistry
What is the transition of a solid to a gas called?
Sublimation
What kind of chromatography is paper chromatography?
Thin layer chromatography
At which level of the fractional distillation column do the lighter hydrocarbons, such as methane and ethane, get condensed?
The top
We perform Gas Chromatography on a liquid mixture containing 3 compounds. How many peaks do we expect to observe from our detector?
4
What is matter?
Anything that has mass and occupies space
One mole water of which phase occupies the largest volume?
Gas
Name the three kinds of chromatography
Thin - layer chromatography, gas chromatography, column chromatography
Which part of the fractional distillation column are we more likely to collect fuel for cars? (The top, the middle or the bottom?)
The top
What is the basis of separation for an ion exchange chromatography column?
Particle Charge
You are performing SEC on a mixture containing 3 different types of molecules. Molecule A is 5A in diameter, molecule B is 2.5A in diameter, and molecule C is 7A in diameter. In what order will they pass through the column?
C then A then B
What physical factors can influence the states of matter, causing substances to transition between solid, liquid, and gas phases?
Temperature and Pressure
True or False: The retention factor for a compound in thin layer chromatography can be greater than 1
False: The formula is distance traveled by the sample / distance traveled by the solvent.
What does the viscosity of the hydrocarbon tell us?
How easily it flows
Would you expect to observe more variation in the retention factor or retention time?
Retention factor
Name the 5 types of column chromatograhy
liquid - liquid, liquid-solid, ion exchange, size exclusion, affinity chromatography
How many phases are in a sealed container full of oversaturated sugar solution?
Two Phases
You perform liquid chromatography on a mixture of two compounds. One is very polar, the other is nonpolar. Which of the compounds will have a higher Rf after performing the chromatography experiment?
The non-polar compound
Which type of hydrocarbon is better suited for use in a lubricant?
Hydrocarbons with shorter chains
What factors can influence the width of the peak in SEC?
Diffusion (along column / due to geometry) , incomplete mass transfer
Chromatography separates the components into two homogenous phases. What are they?
Stationary Phase and the Mobile Phase
Define a Phase
A distinct and homogeneous state of a system with no visible boundary separating it into parts.
What two key features determine the retention time of a component in GC?
Size and Boiling point
What term refers to an imaginary stage inside the distillation column that aids in separating substances based on their vaporization characteristics?
Theoretical plate
Which chromatography method would you use to separate the materials in the following sample:
The sample consists of water with a complex mixture of trace levels of organic compounds. The compounds can be grouped into broad categories of organic acids, organic bases and neutral organics. The desire is to have three solutions at the end, each in methylene chloride, one of which contains only the organic acids, the second contains only the organic bases, the third contains only the neutrals.
Liquid - Liquid Chromatography
You have reason to believe that most of the host cell proteins (HCPs) in a solution are negatively charged at a solution pH of 7. Your target biologic has a pI of 8.9. Could you use an anion exchange column to selectively purify your target biologic?
Yes - Operate in flow-through mode: operate the column at a pH of 7 and allow the target biologic to flow through in the eluent