Introducing Science (1) Textbook: New Science Discovery For Lower Secondary, Volume 1, 2 nd Edition,...
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Introducing Science Introducing Science (1)(1)Textbook: New Science Discovery For Lower Secondary, Textbook: New Science Discovery For Lower Secondary, Volume 1, 2Volume 1, 2ndnd Edition, Chapter A1 Introducing Science Edition, Chapter A1 Introducing Science
What are we going to What are we going to learn in this chapter?learn in this chapter?
What is Science?What is Science?
Laboratory Dos and Don’tsLaboratory Dos and Don’ts
Learn the names and how to use Learn the names and how to use common laboratory apparatuscommon laboratory apparatus
How does the Bunsen burner How does the Bunsen burner work? work?
WHAT IS THE MEANING OF APPARATUS?WHO INVENTED THE BUNSEN BURNER?
What is Science?What is Science?
________ is the study of things in this ________ is the study of things in this world.world.
People who are involved in studying the People who are involved in studying the
world are known as ________ . They world are known as ________ . They
________ and interpret what they ________ and interpret what they see/hear/see/hear/
feel/sense through _______________. feel/sense through _______________. Fill in the missing words: Scientists, Observe, Scientific Inquiry, Science
Science
scientific inquiry
observe
scientists
What is Science?What is Science?
Science is the study of Science is the study of thingsthings in this world. in this world.
Do you know all the following terms?Do you know all the following terms?
PhysicsPhysics ChemistryChemistry BiologyBiology
ZoologyZoology AgricultureAgriculture GeologyGeology
BotanyBotany Meteorology Meteorology SeismologySeismology
HistologyHistology OrnithologyOrnithology IchthyologyIchthyology
Search for the meaning of these branches of science @ http://www.buzzle.com/articles/branches-of-science.html
What is Science? What is Science?
Main Branches of Science:Main Branches of Science:
Physics: Study of interaction Physics: Study of interaction between forces and energybetween forces and energy
What is Science?What is Science?
Chemistry: Study of properties, Chemistry: Study of properties, composition and reactions of composition and reactions of substances.substances.
What is Science?What is Science?
Biology: Study of structure, Biology: Study of structure, growth and function of living growth and function of living things. things.
What is Science?What is Science?
Other Branches of Science: Other Branches of Science: Zoology, Botany, Agriculture, Zoology, Botany, Agriculture, Geology, Meteorology, Medicine, Geology, Meteorology, Medicine, Epidemiology Epidemiology
What is epidemiology?How did the study of epidemiology help in the containment of SARS (2003) and H1N1 (2009)?
What is Science?What is Science?
FAMOUS SCIENTISTSFAMOUS SCIENTISTS
PAST OR PRESENT??PAST OR PRESENT??John DaltonJohn Dalton James WatsonJames Watson
Alexander FlemingAlexander Fleming Gregor MendelGregor Mendel
Stephen ChuStephen Chu Jane Goodall Jane Goodall
PAST!! (1766 – 1844) Researched on atomic theory and colour blindness
PRESENT!! (Born 1928 ) Co-discover of the DNA structure
PAST!! (1881 – 1955) Discovered penicillin which evolved into modern day antibiotics
PAST!! (1822 – 1884) Researched on the inheritance of traits from genes
PRESENT!! (Born 1948) Research on nuclear energy as an alternative for fossil fuel. Also U.S. Secretary of Energy.
PRESENT!! (Born 1934) World’s foremost expert on chimpanzees
What is Science? What is Science?
ANYONE CAN BE A SCIENTIST!!! ANYONE CAN BE A SCIENTIST!!!
TRAITS OF SUCCESSFUL SCIENTISTS TRAITS OF SUCCESSFUL SCIENTISTS
Curiosity – They want to find out things Curiosity – They want to find out things they do not understand. they do not understand.
Creative – They use different methods to Creative – They use different methods to achieve their aims. achieve their aims.
Perseverance – They do not give up even Perseverance – They do not give up even if they fail with a certain method. if they fail with a certain method.
The LaboratoryThe Laboratory
The laboratory is the workplace of The laboratory is the workplace of scientists. scientists.
We will be performing our practical We will be performing our practical work in our own laboratories. work in our own laboratories.
Some labs are small and simple and Some labs are small and simple and some have expensive machineries. some have expensive machineries.
However, all laboratories follow some However, all laboratories follow some important rules. important rules.
Rules in the LaboratoryRules in the Laboratory
DO OR DON’T???DO OR DON’T???Listen to given instructions carefully
Wear safety goggles Keep the laboratory neat and tidy
Wash your hands after an experiment
Run in the laboratory
Taste the chemicals
Pour leftover chemicals back into the containers
Point the flask towards your friend while heating the content inside
Rules in the LaboratoryRules in the Laboratory
DODOListen to instructions before proceeding Listen to instructions before proceeding
with the experiment. with the experiment.
Keep the laboratory benches clean and Keep the laboratory benches clean and tidy. tidy.
Wear safety goggles.Wear safety goggles.
Wash your hands after an experiment. Wash your hands after an experiment.
Rules in the LaboratoryRules in the Laboratory
DON’TDON’TRun in the laboratory. Run in the laboratory.
Taste the chemicals. Taste the chemicals.
Point the flask towards your friend Point the flask towards your friend while heating the contents inside. while heating the contents inside.
Pour leftover chemicals back into the Pour leftover chemicals back into the containers. containers.
Rules in the laboratoryRules in the laboratory
NEVER BRING FOOD OR EAT IN THE LAB ! ! !
Rules in the laboratoryRules in the laboratory
ALWAYS WEAR SAFETY GOGGLES ! ! !
Rules in the laboratoryRules in the laboratory
BE SAFE IN THE LABORATORY ! ! !
Hazard Warning Hazard Warning SymbolsSymbols
Hazard warning symbols are important Hazard warning symbols are important because they tell you what to look out because they tell you what to look out for in a hazardous environment. for in a hazardous environment.
Toxic Flammable
Explosive
What are the symbols for corrosive, radioactive, biohazardous and irritating/harmful substances?
Corrosive Flammable Explosive
Harmful Irritant Environmental hazard
biohazard Radioactive Toxic
Hazard Warning Hazard Warning SymbolsSymbols
1.1. What should we do when we What should we do when we encounter a flammable substance? encounter a flammable substance?
2.2. What would an irritant substance do What would an irritant substance do to us?to us?
3.3. Is it advisable to work long hours with Is it advisable to work long hours with a radioactive substance? Why? a radioactive substance? Why?
Laboratory Apparatus Laboratory Apparatus
Instruments and equipment used in the laboratory is termed as apparatus.
wire gauze
tripod stand
Bunsen burner
retort stand
dropper
test-tube holder
beaker
test-tubes
test-tube rack
Laboratory ApparatusLaboratory Apparatus
1.1. Which apparatus can measure up to an Which apparatus can measure up to an accuracy of 0.1 cmaccuracy of 0.1 cm33? ?
2.2. Why does the conical flask have a narrow Why does the conical flask have a narrow neck? neck?
3.3. What do we use to transfer chemical What do we use to transfer chemical substances without spillage? substances without spillage?
4.4. Why do you think the wire gauze is used Why do you think the wire gauze is used other than the reason of supporting the other than the reason of supporting the apparatus during heating?apparatus during heating?
The Bunsen burner is used in many processes where heating is required such as crystallization, distillation and testing of gases.
However, the use of the Bunsen burner is not as simple as it seems, there are several techniques to learn about using the Bunsen burner.
The Bunsen BurnerThe Bunsen Burner
The Bunsen BurnerThe Bunsen Burner
Collar
Air-hole
Stand/base
Barrel
Gas jet
Rubber tubing Gas tap
Parts of a Bunsen Burner1. Barrel2. Gas jet3. Collar4. Air-hole5. Gas tap6. Rubber
tubing7. Stand/base
The Bunsen BurnerThe Bunsen BurnerFunction of Each Part
Chimney/Barrel: Raises the flame to Chimney/Barrel: Raises the flame to suitable heightsuitable height
Collar: To regulate the air-flow entering Collar: To regulate the air-flow entering the burnerthe burner
Air-hole: Allows air into the burnerAir-hole: Allows air into the burner
Gas jet: Enables gas to rush out and Gas jet: Enables gas to rush out and draw in airdraw in air
Base/Stand: Supports the burnerBase/Stand: Supports the burner
Gas tap: Control the gas flowGas tap: Control the gas flow
Types of Flames
Luminous Flame Non-Luminous Flame
It is formed when the air-hole is open.
It is formed when the air-hole is closed
Appearance of Flames
Non-luminous blue zone(Due to complete combustion of gas)
Blue zone (Unburnt gas)
Luminous yellow zone(Due to partial combustion of gas)
Black soot produced
Flickers, easily seen
Steady, not easily seen
Hottest zone is at the tip of the unburnt gas zone
LUMINOUS NON-LUMINOUSAir-hole Closed Open
Colour Yellow Blue
Description Flickers and is easily seen
Steady and is not easily seen
Temperature
High (500oC) Very high (900oC)
Produces Soot?
YES NO
Used for Heating?
NO YES
Complete Combustion of Gas?
NO YES
The Bunsen BurnerThe Bunsen Burner
1.1. Why do we not use the luminous Why do we not use the luminous flame for heating?flame for heating?
2.2. Why does the non-luminous flame Why does the non-luminous flame appear blue? appear blue?
3.3. Where is the hottest part of the non-Where is the hottest part of the non-luminous flame? luminous flame?
4.4. What happens during a strike-back What happens during a strike-back and what should we do? and what should we do?