EXPERIMENT 2

Question 1

Specific procedures/techniques have been developed so the chemist does not introduce impurities through carelessness or endanger himself or those who work with him/her. We call these procedures what?

Answer 1

COMMON LABORATORY OPERATIONS; LABORATORY TECHNIQUES

Question 2

Systematic procedures by which a complex work or scientific piece of work is accomplished.

Answer 2

COMMON LABORATORY OPERATIONS; LABORATORY TECHNIQUES

Question 3

HANDLING LIQUID SOLUTIONS

Reagent bottles come in various sizes with various kinds of covers or stoppers. What do you do with the stoppers?

Answer 3

NEVER LAY DOWN THE STOPPERS OF REAGENT BOTTLES ON THE TABLE

Question 4

HANDLING LIQUID SOLUTIONS

For reagent bottles that have CORKS or SCREW CAPS for stoppers, _________ and __________ the cover in your hand.

Answer 4

REMOVE; KEEP

Question 5

HANDLING LIQUID SOLUTIONS

For stoppers that have handlers, _______ the stopper at the handler with _______ and _______ fingers.

Answer 5

CLIP; INDEX; MIDDLE

Question 6

HANDLING LIQUID SOLUTIONS

Note the position of the stopper. Pour slowly. To avoid splashing, use a ____ _____ to guide the liquid as if it flows out.

Answer 6

GLASS ROD

Question 7

HANDLING LIQUID SOLUTIONS

Always put the stopper back in the bottle after using it. If the reagent spills down the side of the bottle, ______ the side with _____ _____, not allowing the water to enter the bottle.

Answer 7

RINSE; TAP WATER

Question 8

HANDLING OF SOLIDS

Never handle solids with?

Answer 8

WET HANDS

Question 9

HANDLING OF SOLIDS

A clean and dry ______ can remove solids from the reagent bottle.

Answer 9

SPATULA

Question 10

MIXING LIQUID SOLUTIONS

When mixing acid and water in preparing a dilute solution, REMEMBER, IT IS ________ TO _________, NOT __________ TO __________.

Answer 10

ACID TO WATER; WATER TO ACID

Question 11

MIXING LIQUID SOLUTIONS

In a test tube. What action is taken to mix the solution?

Answer 11

FLICKING ACTION OF THE FINGER

Question 12

MIXING LIQUID SOLUTIONS

In an Erlenmeyer Flask. Solutions are mixed with a ____ _____ and _____ of the flask.

Answer 12

GENTLE SWIRL; ROTATION

Question 13

MIXING LIQUID SOLUTIONS

In a beaker. A _____ ______ is used to mix the solution.

Answer 13

STIRRING ROD

Question 14

MIXING SOLIDS

Before mixing solids, the solid must be in a _____ _____ state. Mixing is done using a ________ and _________.

Some substances or materials react because of the _______ _____ _________ resulting from the grinding.

Answer 14

FINELY DIVIDED; MORTAR AND PESTLE

HEAT OF FRICTION; GRINDING

Question 15

MIXING SOLIDS

A mortar and pestle. What motion should you use?

Answer 15

FIRM GRIDING MOTION; NOT A POUNDING MOTION

Question 16

MIXING SOLIDS

A tightly covered vial or bottle; What do you do to mix?

Answer 16

SHAKE FOR AT LEAST 5 MINUTES

Question 17

HEATING LIQUIDS

Liquids are heated in a:

Answer 17

a. TEST TUBE
b. BEAKER
c. FLASK

Question 18

HEATING LIQUIDS

a.) TEST TUBE

Hold the test tube with a _____________ and __________ the test tube about ______ degrees from the horizontal, then apply a small flame __________ the liquid surface, and agitate the test tube from side to side. Do not point the test tube in the direction of anyone.

Answer 18

TEST TUBE HOLDER; INCLINE; 30; BELOW

Question 19

HEATING LIQUIDS

b.) BEAKER

Place a _____________ in the beaker or use __________________ or ______________ to reduce the bumping of the liquid. A _____________ is placed over the iron ring to support the beaker and to even out the heat applied to the beaker.

Answer 19

STIRRING ROD; BROKEN PORCELAIN; GLASS BEADS; WIRE GAUZE

Question 20

HEATING LIQUIDS

c.) FLASK

______ the flask with the solution over a small flame. The flask can be held with a ____________ or a strip of paper folded several times, as in the drawing. A set-up similar to the beaker can be used.

Answer 20

SWIRL; UNIVERSAL CLAMP

Question 21

When an insoluble solid is dense or heavy, it settles quickly to the bottom of the container. The clear or _____________ that separates is carefully poured out without disturbing the solid. What is this technique called?

Answer 21

DECANTATION

Question 22

If the solid is fine or does not quickly settle down, what process is preferred?

Answer 22

FILTRATION

Question 23

This process or technique separates a mixture’s precipitate or insoluble solid components from the liquid component. This technique uses filter paper and a runner to hold the filter paper.

Answer 23

FILTRATION

Question 24

In filtration, where should the tip of the funnel be at the beaker?

Answer 24

TOUCHES THE SIDE OF THE BEAKER

Question 25

FILTRATION Use this to support the funnel if the iron ring is too large.

Answer 25

WIRE TRIANGLE

Question 26

FILTRATION The solid material trapped in the filter paper is called the __________________; the liquid that flows through the funnel is the _____________.

Answer 26

RESIDUE; FILTRATE

Question 27

FILTRATION If it is necessary to purify the precipitate, wash it with ________________ from a wash bottle.

Answer 27

DISTILLED WATER

Question 28

This is a process or technique of separating the dissolved solid from the liquid solvent. This technique is used if the liquid is not recovered, but if the liquid is needed, then distillation is preferred.

Answer 28

EVAPORATION

Question 29

STEPS IN EVAPORATION 1) Place the solution in an ___________. 2) Heat over a _______ until the liquid is gone. Use a small flame so that the mixture does not boil to avoid loss of materials. 3)

Answer 29

EVAPORATING DISH; FLAME

Question 30

This uses the unique property or characteristic of pure substances where it can change its physical state from solid to gas without visible evidence of the liquid state. This technique separates the components of solid mixtures that quickly evaporate.

Answer 30

SUBLIMATION

Question 31

SUBLIMATION 1) Place the solid mixture in a ______. 2) Place ________ in a round bottom flask. 3) Assemble the set-up as illustrated. 4) Apply gentle heating.

Answer 31

BEAKER; COLD WATER

Question 32

What apparatus is needed for FILTRATION?

Answer 32

1) FUNNEL 2) FILTER PAPER 3) BEAKER 4) ERLENMEYER FLASK

Question 33

What apparatus is needed for DECANTATION?

Answer 33

1) BEAKER 2) GLASS STIRRING ROAD 3) SEPARATORY FUNNEL

Question 34

What apparatus is needed for EVAPORATION?

Answer 34

1) EVAPORATING DISH 2) WATCH GLASS 3) HOT PLATE/BUNSEN BURNER 4) WIRE GAUZE

Question 35

What apparatus is needed for SUBLIMATION??

Answer 35

1) BUNSEN BURNER 2) TRIPOD 3) FLASK 4) BEAKER 5) WIRE GAUZE

Question 36

GIVE AN APPLICATION OF FILTRATION

Answer 36

1) Water Purification: Removes dirt, sand, and bacteria from drinking water. 2) Coffee Making: A coffee filter separates coffee grounds from liquid coffee. 3) Air Purifiers: HEPA filters trap dust and allergens from the air. 4) Pharmaceutical Industry: Used to filter out impurities from drugs. 5) Wastewater Treatment: Separates solid pollutants from sewage water.

Question 37

GIVE AN APPLICATION OF DECANTATION

Answer 37

1) Oil-Water Separation: Used in petroleum refineries to remove water from crude oil. 2) Winemaking: Separates wine from sediment (lees) before bottling. 3) Removing Sand from Water: Sand settles at the bottom, and clear water is poured out. 4) Blood Plasma Separation: In medical labs, plasma is separated from blood cells after centrifugation.

Question 38

GIVE AN APPLICATION OF SUBLIMATION

Answer 38

1) Purification of Substances: Used to purify substances like iodine and naphthalene. 2) Dry Ice (CO₂) in Refrigeration: Dry ice sublimates into gas, keeping items cool without leaving liquid residue. 3) Air Fresheners: Solid air fresheners (naphthalene balls, camphor) sublimate over time. 4) Forensic Science: Iodine sublimation is used to reveal fingerprints.

Question 39

GIVE AN APPLICATION OF EVAPORATION

Answer 39

1) Salt Production: Seawater is evaporated in salt pans to extract salt. 2)Sugar Crystallization: Used in sugar refineries to separate sugar from sugarcane juice. 3) Drying Clothes: Water evaporates from wet clothes when left in the sun. 4) Concentrating Fruit Juices: Water is evaporated to make juice concentrates. 5) Cooling Mechanism: Sweat evaporates from the skin, cooling the body.