Forensic Chemistry/Toxicology

The procedure called liquid-liquid extraction is used to separate one solid material from another

• When at least two grams of material are present. 

• When all material is liquid.

• No matter how much material is present.

• When there are no presents    

The pH of pure water is

• 14

• 7

• 3

• 10

A solution with a pH of 5 is

• Alakaline

• Very alkaline

• Acid

• Very Acid

In order to effectively dissolve a solute in a solvent, both should be

• Polar

• Non polar

• Bipolar

• quiasipolar

Gasoline and water dissolve readily in each other because

• they have a chemical affinity

• they don't repel each other

• they repel each other

• they don’t dissolve in each other

Forensic labs rarely use Gas Chromatography

• it is too expensive

• they don’t know how to use it correctly

• It is unnecessary for most cases

• Actually they use it regularly

Separating a mixture of iron powder and sand would require

• sieve

• funnel

• magnet

• heat

If you boil sea water until there is no more water in it you would be left with

• fish slime

• seashells

• salt and other materials

• sand

Tags

NGSS.HS-ESS2-5

Chromatography is used because

• Is a good method for separating compounds

• Colors represent compounds

• Compounds are colorful

• Light reflection shows us the type of compound in the substance

The phases of chromatography are

• Mobile and Solid

• Stationary and Mobile

• Solid and Separatory

• Immiscible and Elution