Lab Assistant Practice

If an aqueous solution has H₃O concentration of 1 x 10^-9 mol/L, the solution is:

• acidic and litmus paper will turn red

• basic and litmus paper will turn red

• acidic and litmus paper will turn blue

• basic and litmus paper will turn blue

What type of liquid is pentanol?

• Trihydroxil alcohol

• Cyclic hydrocarbon

• Polymer

• Primary alcohol

What is the characteristic of most organic compounds?

• Low melting point

• Intermolecular force

• Highly soluble in water

• Ionic

Which device records the amount of light coming through a sample in a Spect20?

• Sample well

• Injector

• Diverter

• Detector

According to the ASTM, an acceptable elapsed time for a viscosity test is how many minutes?

• 1 to 3

• 5 to 10

• 10 to 12

• 12 to 15

1s ²2s ²2p⁶3s ²4s² This electron configuration has an incomplete:

• Second principle energy level

• Second sublevel

• Third principle energy level

• Third sublevel

3 things that must appear properly kept in a laboratory databook page are assistant's signature, date, and:

• Title of witness

• Procedure

• Witness's signature

• Next scheduled activity

What does the 50 in the following signify: LD50

• Lethal dosage that killed everyone in the population over the age of 50

• Lethal dosage since 1950

• Lethal dosage that caused the death of 50% of an animal population

• Lethal dosage that killed everyone in the population under the age of 50

The only time g = mL is when:

• The substance is alcohol

• Acids are being made

• Bases are being made

• Water is the solvent

According to EPA, when taring for TSS and TDS how accurate in grams must the weight be?

• 0.005

• 0.05

• 0.5

• 5