AY 2425 S3 Experimental Techniques

Scientific Method

the lab is the home of Chemistry.

​You study Chemistry....

​you deal with lab works and scientific methods.

• steps in Scientific Methods

• Laboratory apparatus and their uses, including analyzing, correcting error of apparatus, drawing graph

Reorder

Reorder the following :

Scientific Methods Steps

• observe and question

• make a hypothesis

• plan an experiment to test the hypothesis

• carry out the experiment and records the results

• analyse the results

1

2

3

4

5

• 1
• 2
• 3
• 4
• 5

​planning of experiment : requires variables

​independent variables : variables that always changed

​dependent variables : the result when independent variables applied to an experiment

skills you use ​

• thinking

• observing

• using apparatus and techniques

• working accurately

• doing some maths

• writing up

​problem

​many salts increase in solubility as the temperature increases.

plan an experiment to see if this is true, using the salt potassium chloride as an example

Multiple Select

tick apparatus you need to carry out the investigation

• thermometer

• stopwatch

• beaker

• balance and weighing boat

• water bath

Match

Match the following

what are the independent, controlled and dependent variables of the experiment?

• independent variables

• dependent variables

• controlled variables

temperature of the water

mass of solid added that fully dissolves

volume of water

• temperature of the water

• mass of solid added that fully dissolves

• volume of water

Reorder

Reorder the following

describe how you will carry out the experiment. give possible volumes and masses of the substances used

• place 50 cm3 or 100 cm3 of water in beaker

• heat water to fixed temperature

• add small weighed amount of solid KCl to water and stir

• keep adding small weighed amount until no more dissolves

• repeat at different temperature

1

2

3

4

5

• 1
• 2
• 3
• 4
• 5

laboratory rules

apparatus and its uses

Match

Match the following

(apparatus to measure volume)

beaker glass

burette

volumetric pipette

volumetric flask

measuring cylinder

• beaker glass

• burette

• volumetric pipette

• volumetric flask

• measuring cylinder

Match

Match the following

match the picture with its correct name

thermometer

stopwatch

filter funnel

retort stand and clamps

crucible

• thermometer

• stopwatch

• filter funnel

• retort stand and clamps

• crucible

Match

Match the following

match the picture with its uses

measuring temperature

measuring time

transfer liquid and filter solid

hold the burette

heat solid samples

• measuring temperature

• measuring time

• transfer liquid and filter solid

• hold the burette

• heat solid samples

Match

Match the following

match the picture and its correct name

conical flask

test tubes and test tubes rack

dropping pipette

mortar and pestle

round bottomed flask

• conical flask

• test tubes and test tubes rack

• dropping pipette

• mortar and pestle

• round bottomed flask

Match

Match the following

the apparatus and its name

tripod stand, wire gauze, Bunsen burner

triangle clay

bulb filler

crucible tongs

top pan balance

• tripod stand, wire gauze, Bunsen burner

• triangle clay

• bulb filler

• crucible tongs

• top pan balance

Multiple Choice

What is the reading of the meniscus of measuring cylinder?

• 36.0 cm3

• 45.0 cm3

• 35.0 cm3

• 30.5 cm3

Match

Match the following

hazard symbol

flammable

toxic

explosive

damage to aquatic environement

corrosive

• flammable

• toxic

• explosive

• damage to aquatic environement

• corrosive

Match

Match the following

hazard symbol

oxidiser

radioactive hazard

harmful

• oxidiser

• radioactive hazard

• harmful

Multiple Choice

Which of the following is the correct laboratory rule?

• Eating in the laboratory while doing practical during lunch time

• Running in the laboratory when he is in a hurry

• Poking the electrical power points with sharp objects

• Using the apparatus in the laboratory only when told to do the science teacher

Multiple Choice

A student working in a laboratory accidentally spilled concentrated hydrochloric acid on his hand. The most practical thing to do is __________.

• To go to the hospital immediately

• To rub the hand with a wet towel

• To rub the hand with a dry towel

• To wash the hand quickly under running water

Multiple Choice

Answer the question

• D

• B

• A

• C

Multiple Choice

• A

• B

• C

• D

Multiple Choice

what is the reading on this burette?

• 4.40mL

• 3.50mL

• 3.60mL

• 4.50mL

Match

Match the following

apparatus and its most appropriate use

measure 20.50 cm3 acid in titration accurately

transfer 50 cm3 of solution to conical flask accurately

make fixed amount such as 250 cm3 of solution

measure volume of liquid, such as 10.0 cm3 accurately (used in quantitative experiment)

measure volume approximately

• measure 20.50 cm3 acid in titration accurately

• transfer 50 cm3 of solution to conical flask accurately

• make fixed amount such as 250 cm3 of solution

• measure volume of liquid, such as 10.0 cm3 accurately (used in quantitative experiment)

• measure volume approximately

volume of gas

​

volume of gas

​

Multiple Choice

which gas that best prepared by displacement of water

• sulfur dioxide gas

• hydrogen chloride gas

• Hydrogen gas
• chlorine gas

Draw

There is one error in the way the apparatus has been set up.

On the diagram draw a circle around the error in the apparatus.

Draw

(a) Indicate with an arrow on the diagram where heat should be applied. [1]

(b) circle two errors in the experiment

solute, solvent, solution

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solute, solvent, solution

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saturated solution

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