(P) L2: Reagent Preparation

Question 1

T or F: Most reagents come in their diluted form

Answer 1

False (concentrated)

Question 2

This piece of equipment weighs out desired amounts of chemicals such as powder or liquid reagents especially if it’s less than 0.1 grams

Answer 2

Analytical Balance

Question 3

T or F: Use regular paper when measuring powder reagents

Answer 3

False (baking or wax paper)

Question 4

You place chemicals into appropriate-sized beakers using this device to guide the liquid

Answer 4

Stir Bar

Question 5

When using this piece of equipment to dissolve solutes, add less than the required volume solvent first before adding the other half

Answer 5

Graduated Cylinder

Question 6

If you are using water, what is the appropriate decontaminated form to use in a laboratory?

Answer 6

Double-distilled

Question 7

This sterilizes the solution, reagents, and equipment

Answer 7

Autoclave

Question 8

Give the appropriate parameters for the autoclave

Answer 8

Temperature: 121ºC
Duration: 20-30 minutes
Pressure: 15 psi

Question 9

This traps the unsterile particles to give way for the sterile solution; make sure the paper is single use only—used for only small amounts of liquid

Answer 9

Filtration

Question 10

What is the paper measurement for filter sterilization?

Answer 10

0.22 or 0.45 µm

Question 11

A standard but essential instrument that precisely and accurately transfers volumes of liquid within small microliters in volume

Answer 11

Micropipette

Question 12

What is the difference between a single-channeled and a multi-channeled micropipette?

Answer 12

Single-channeled only aspirates one volume while multi-channeled has multiple pipette tips

Question 13

What is more commonly used in the laboratory, single or multi-channeled micropipette?

Answer 13

Single

Question 14

T or F: The single-channeled micropipette reduces workload compared to the multi-channeled

Answer 14

False (used for large volume of samples)

Question 15

What kind of micropipettes are used where it aspirates a certain amount of liquid and dispenses almost the exact amount of air?

Answer 15

Air displacement micropipettors

Question 16

Parts of a micropipette:
> it is connected to the plunger and helps in measurement

Answer 16

Piston and cylinder system

Question 17

Parts of a micropipette:
> pushes the air volume equal to the liquid to be aspirated

Answer 17

Plunger

Question 18

T or F: The plunger adjusts the volume by turning up or down to decrease or increase the volume level

Answer 18

False (clockwise and counterclockwise)

Question 19

Parts of a micropipette:
> some pipettes have this same function with their plunger

Answer 19

Volume adjustment knob

Question 20

Parts of a micropipette:
> it pushes the ejector arm to remove the pipette tips to prevent contact upon disposal

Answer 20

Tip ejector

Question 21

Parts of a micropipette:
> it offers fitting for the pipette tips

Answer 21

Tip cone

Question 22

T or F: The pipette should be held in a vertical position

Answer 22

True

Question 23

What is the appropriate immersion depth in forward pipetting?

Answer 23

1-3mm

Question 24

What is the appropriate immersion depth for REVERSE pipetting?

*note: it has it’s own depth acc. to the ppt

Answer 24

2-5mm below the solution surface

Question 25

What happens when you immerse the pipette too deeply?

Answer 25

Potential hole blockage

Question 26

What happens when you immerse the pipette too shallow?

Answer 26

Potential air bubbles

Question 27

How much should the container be tilting diagonally?

Answer 27

10º-40º

Question 28

A P20 pipette can hold what volume range?

Answer 28

2-20

Question 29

A P200 pipette can hold what volume range?

Answer 29

20-200

Question 30

A P1000 pipette can hold what volume range?

Answer 30

200-1000

Question 31

A P5000 pipette can hold what volume range?

Answer 31

1000-5000

Question 32

What is the tip color for a P20 pipette?

Answer 32

Yellow

Question 33

What is the tip color for a P200 pipette?

Answer 33

Yellow

Question 34

What is the tip color for a P1000 pipette?

Answer 34

Blue

Question 35

What is the tip color for a P5000 pipette?

Answer 35

White

Question 36

T or F: It is better to choose the smallest pipette capable of handling your desired volume

Answer 36

True

Question 37

Forward or Reverse Pipetting? > used more commonly for liquid samples

Answer 37

Forward

Question 38

Forward or Reverse Pipetting? > used more frequently for viscous samples such as oil and blood

Answer 38

Reverse

Question 39

When do you press until the second stop for forward pipetting?

Answer 39

When dispensing

Question 40

When do you press until the second stop for reverse pipetting?

Answer 40

Before aspiration

Question 41

T or F: You can clean the micropipette tip orifice using tissues

Answer 41

False (the tissue can possibly absorb the liquid contents inside the pipette making the volume not exact anymore)

Question 42

T or F: Set the volume of the micropipette to the maximum capacity before use

Answer 42

False (after)

Question 43

T or F: Always use a new tip for each new substance

Answer 43

True