cluster 1 set a Flashcards
(42 cards)
The following will cause drift errors in an analytical balance except:
a. Balance door is open.
b. Balance is not levelled.
c. Air currents are present in the laboratory.
d. Temperature of the balance and the sample to be weighed is the same.
Balance door is open.
It is a document that provides useful information on the chemical hazards, advice on safe
handling, use and storage, and the emergency measures to be followed in case of an accident. It usually contains 16 headings.
a. Certificate of Analysis
b. Product Specification
c. Safety Data Sheet
d. Environmental Compliance Certificate
Safety data sheets
Type of chemical that can cause an allergic reaction in the airways following inhalation of the chemical.
a. Oxidizer
b. Corrosive
c. Carcinogen
d. Respiratory Sensitizer
Respiratory Sensitizer
Ammonia solution can be stored with the following chemicals except for:
a. acetic acid solution
b. sodium hydroxide solution
c. 2-propanol solution
d. cyclohexane solution
acetic acid solution
First consideration for chemical storage shall be based on its:
a. frequency of usage
b. compatibility with other chemicals
c. size of the container
d. alphabetical order
compatibility with other chemicals
In operating a UV-Vis spectrophotometer, the following shall be done, except for:
a. Before turning on the power, check if the sample holder does not contain anything.
b. Keep the sample compartment open during measurement.
c. If there are any spillage that gets onto the instrument, immediately wipe it away.
d. After turning on, allow the spectrophotometer to initialize and stabilize according to its user
manual.
Keep the sample compartment open during measurement.
In maintenance and storage of pH meters, which of the following procedure shall not be done?
a. To keep the electrode bulb moist during storage, store the electrode in distilled water.
b. Rinse pH electrodes in between measurements.
c. Blot the electrode dry after rinsing the pH electrodes.
d. Mild soap solution may be used in general cleaning of the electrodes
To keep the electrode bulb moist during storage, store the electrode in distilled water.
In using fume hoods, the following shall be done, except for:
a. Ensure the exhaust is operating before using the hood.
b. The hood shall be kept closed, except during apparatus set-up or when working within the
hood.
c. The hood may be used as a permanent storage area for volatile chemicals when an
appropriate storage cabinet is not available.
d. Items contaminated with odorous or hazardous materials should be removed from the hood
only after decontamination or if placed in a closed outer container to avoid releasing
contaminants into the laboratory air.
The hood may be used as a permanent storage area for volatile chemicals when an appropriate storage cabinet is not available.
Which of the following does not require a minimum of annual third party calibration?
a. analytical balance
b. drying oven
c. autoclave
d. sets of weights
sets of weights
Which of the following is an oxidizing chemical?
a. potassium dichromate
b. sodium hydride
c. magnesium
d. sodium
potassium dichromate
In starting-up laboratory operations the following should be observed except ________.
a. Turning on the hoods, vents and exhaust fans.
b. Turning the equipment and instruments on.
c. Performing the analysis immediately.
d. Monitoring operating parameters.
Performing the analysis immediately.
- The following must be avoided in using the analytical balance except ______________.
a. Weighing warm objects in the balance.
b. Closing the draft shield before reading the result.
c. Placing the sample not at the center but on the side of the pan.
d. Touching the samples or sample containers with your bare fingers.
Closing the draft shield before reading the result.
- Which of the following must be performed before using the analytical balance?
a. Cleaning the balance and removing sample residues.
b. Determine the sensitivity of the balance using calibration weight.
c. Checking the level of the balance by adjusting the air bubble.
d. All of the above.
All of the above.
- Sealable enclosures containing desiccants used to protect chemicals which
are hygroscopic or which react with water from humidity.
a. Mortar and Pestle
b. Desiccator
c. Evaporating dish
d. Separatory Funnel
Desiccators
- To determine the specific gravity of a liquid, which of the following glass wares should be used?
a. volumetric flask
b. pycnometer
c. pipette
d. graduated cylinder
A hydrometer
Preparation of highly toxic and volatile compounds should be carried out in an efficient
_____________.
a. canopy hood
b. laminar hood
c. fume hood
d. any of the above
A fume hood
- Which of the following shall not be followed when boiling a solution in a hot plate?
a. Make sure that the glass ware being used is heat resistant
b. Inspect the glass ware for cracks before putting it in the hot plate.
c. Add boiling stones to facilitate boiling.
d. When removing the heated material, use polyethylene gloves to protect your hand from
heat.
When removing the heated material, use polyethylene gloves to protect your hand from
heat.
18-20. The absorbance of different concentrations of potassium permanganate determined through UV-Vis Spectrophotometer is shown below.
solving
- The conductivity value of a liquid solution increases as the temperature decreases as a result of higher ion mobility.
FALSE
The alkaline effect is the phenomenon where H+ ions in the gel layer of the pH-sensitive membrane are partly or completely replaced by alkali ions.
TRUE
In pH measurements, if the solution is acidic, the H+ ions diffuse out of the layer and a negative charge is established on the outer side of the membrane.
FALSE
Karl Fischer titrator is used to determine viscosity of liquids.
FALSE
For pipettes marked with To Deliver (TD), a small amount of liquid remaining on the tip should not be blown out.
TRUE
Cuvettes must be cleaned in an ultrasonic cleaning bath.
FALSE
