Jaymee Science S1 Chapter 1 Notes PDF

Jaymee Science S1 Chapter 1 1. What is Science? 1.1 Examples of innovative technologies for the Olympic Games: Medals made from recycled materials 3D-printed running shoes GoalRef Technology Camera technology Smart glasses for cyclists 1.2 Science is the study of phenomena and events in Nature throu...

Jaymee Science S1 Chapter 1 1. What is Science? 1.1 Examples of innovative technologies for the Olympic Games: Medals made from recycled materials 3D-printed running shoes GoalRef Technology Camera technology Smart glasses for cyclists 1.2 Science is the study of phenomena and events in Nature through systematic observation and experimentation. 1.3 Examples of the science branches are physics, chemistry, biology, astronomy, geology, and medicine. 1.4 Scientists and their discoveries and inventions: Scientists Discoveries (D) and inventions (I) Louis PASTEUR Discovered microorganisms and invented Pasteurization and vaccines Marie CURIE Developed early theories of radioactivity Lap-Chee TSUI Contributed to the Human Genome Project Charles KAO Invented optical fibres for telecommunications Charles DARWIN Proposed the theory of evolution Albert EINSTEIN Developed the theory of relativity, which helps understand the Universe Youyou TU Discovered artemisinin that treats malaria 1 Jaymee Science S1 Chapter 1 1.5 Scientific discoveries and inventions have many benefits, but they can also cause harm if not used properly, e.g., Inventions Benefits Harm Nuclear technology Produce electricity Harm and kill many people Plastics Bring us convenience, e.g.., buying takeaways Cause pollution to our environment Smartphones Facilitate communication Addicted to smartphones and reduced physical activity Pesticides Pest control that increases agricultural productivity Adverse effects on ecosystems Antibiotics Disease treatment Antibiotic resistance 2. Natural Resource Management 2.1 The Earth provides us with many natural resources to meet our needs, e.g., stay alive (food, water, and shelter). 2.2 There are two major types of natural resources: renewable (can be replenished continuously) and non-renewable (cannot be replenished in a short time and limited supply). These resources include: Living things, e.g., plants (crops, corn, carrot, leaf vegetables) and animals (fish, pig, cow, chicken) 2.3 Today's challenges: natural resources such as air and water are seriously polluted. Fossil fuels are being used up quickly. Scientific knowledge helps us to manage natural resources well and then support our needs continuously. 2.4 Reforestation aims at planting new trees to restore forests. This helps manage the natural resources of air and plants. 2 Jaymee Science S1 Chapter 1 2.5 Examples of ways to manage and use our natural resources, e.g.: Natural Resources Ways to Manage Examples Light energy from the Sun Use solar panels to change light energy to electrical energy. Used water Purified technology is used to produce reclaimed water from used water. Air (Wind) Reference only Metal ores Reference only Wind Energy converts the kinetic energy of moving wind into electrical energy. Technology likes flotation, are used to separate valuable minerals from waste materials and do ore extraction and processing. Biodiversity assessment is developed to assess ecosystem health and Plants and animals guide conservation Reference only efforts, i.e. variety of species (animals, plants, fungi, etc.) 3 Jaymee Science S1 Chapter 1 3. Development of Technology 3.1 Scientific knowledge can be used to develop technology; for example, engineers apply scientific knowledge to create useful products and techniques. Examples include drones and 3D printing technology. Drone 3D printing technology 4. Integrating and Applying Knowledge and Skills of Different Subjects 4.1 We need to integrate and apply knowledge and skills of science, technology, and mathematics to solve our daily life problems. They are closely related. 5. Limitations of Science 5.1 5.2 There are still some problems that cannot be solved using our present scientific knowledge. Examples: o The Origin of the Universe o The way to cure cancers o Ethics and relationships – an ethical act and a better relationship with friends o Wars – the way to prevent wars Scientific knowledge is subject to change. It may be disproved if new evidence finds it to be wrong in the future. Previous Findings Example 1 Example 2 New Findings The Earth was flat The Earth is round The tongue map was a The tongue has different areas to misconception. Tastes can be detected all over the tongue. detect four tastes, e.g., sweet, bitter, sour, and salty. The fifth taste, "umami 鮮味", is discovered. 4 Jaymee Science S1 Chapter 1 6. Steps in Scientific Investigation Step 1: Observe and ask questions carefully and systematically Step 2: Form a hypothesis (or hypotheses) to explain the observation Step 3: Design and do experiments to test the hypothesis, and then measure accurately and record the experimental results in detail. Step 4: Analyse the experimental results Step 5: Draw a conclusion If the results support the hypotheses, then the results will become scientific knowledge. If results do not support the hypothesis, then modify the hypothesis and redo experiments. Used to explain the observation Ask questions Test the hypotheses 6.1 Scientific knowledge is subject to change. It may be disproved if new evidence is found. 6.2 There are six science process skills scientists use when conducting scientific investigations, including observing, classifying, designing investigations, doing experiments, inferring, and communicating. 7. Types of Scientific Investigations Fair Tests Conducting experiments to test the hypothesis formed. Variables include independent variables, dependent variables, and control variables. Classifying Comparing similarities and differences between objects and sorting those with similarities into groups, e.g., plants, animals, matter (solid, liquid, gas) Pattern Seeking Observing and recording natural phenomena and trying to find a pattern. Commonly used in astronomy and geology. Model Building Representing objects that are too small or too big to see, e.g., DNA model, the solar system 5 Jaymee Science S1 Chapter 1 7.1 Fair tests should be ensured when designing the experiments. All variables (factors) should be kept the same except the one we are investigating. Examples: Not a fair test Not a fair test A fair test Same cup size but different volumes of water Same volumes of water but different cup size Same cup size, same volumes of water Independent variable: materials of cups (one paper cup and one foam cup) Dependent variable: the temperature of the hot drink after 20 minutes Control variables: temperature of water, cup size, and volume of water 8. The Science Laboratory 8.1 A lot of experiments are done in a laboratory, which has different types of equipment and apparatus. We need to follow safety rules in the laboratory. 8.2 Safety equipment has to be used to protect our safety when we are doing experiments. 6 Jaymee Science S1 Chapter 1 8.3 Potential dangers in the laboratory: 8.4 Laboratory Safety Rules DON'Ts DOs 1. Always follow the instructions given by your teacher. 1. Do not enter the laboratory without your teacher's permission. 2. Know the fire escape route. 2. Do not run or play in the laboratory. 3. Read safety precautions before doing an experiment. 3. Do not eat or drink in the laboratory. 4. Do not smell or taste any chemicals unless your teacher asks you to do so. 4. Wear safety goggles when heating or mixing substances. 5. Do not touch hot apparatus. 5. Tie up long hair and tuck in school ties when doing experiments. 6. Do not throw solid wastes into the sink. 6. Wash your hands after completing an experiment. 7. Do not point test tubes containing boiling liquids towards yourself or other students. 7. Keep the laboratory clean and tidy. 8. Report all accidents to your teacher immediately. 7 Jaymee Science S1 Chapter 1 9. Hazard Warning Symbols 9.1 Hazard warning symbols warn us of the potential dangers of the chemicals. They may be flammable, corrosive, explosive, toxic, harmful, or irritant. We need to handle all hazardous chemicals with care. 8 Jaymee Science S1 Chapter 1 10. Handling Some Common Laboratory Accidents 10.1 We need to keep calm and tell the teacher immediately. Also, follow the teacher's instructions to handle different accidents. 11. Handling a Fire in the Laboratory 11.1 Conditions for a fire to start include fuel, oxygen, and a high temperature. These three conditions make up the FIRE TRIANGLE. The fire goes out if oxygen is removed. The fire goes out if the high temperature is lowered or removed, e.g., by water. The fire goes out if fuel is removed. 9 Jaymee Science S1 Chapter 1 11.2 Methods of Putting Out a Fire Method How it works Beating the burning plants stops the supply of oxygen to the fire. Spraying water on the fire lowers the high temperature. Cutting down the trees can remove the fuel and so the fire cannot spread. 11.3 Using a Fire Extinguisher to Put Out a Fire in the Laboratory 11.4 Three types of fire extinguishers: Carbon dioxide Used on electrical fires or fires caused by flammable liquids Water type Used on fires caused by woods, textiles, and papers Dry powder type used on most fires 10 Jaymee Science S1 Chapter 1 11.5 The conditions removed to put out the fire: Fuel High Temperature High Temperature Oxygen 12. Common Laboratory Apparatus 12.1 Apparatus for Holding Substances 11 Jaymee Science S1 Chapter 1 12.2 Apparatus for Heating 12.3 Other Apparatus (SPELL THESE WORDS) We use different apparatus to do experiments. 12 Jaymee Science S1 Chapter 1 12.4 Vertical Section Diagrams for Apparatus: We draw vertical diagrams of the apparatus to show the experiment set-up. 13 Jaymee Science S1 Chapter 1 13. Using Measurement Instruments 13.1 Past Today Measuring Length Arms Ruler Measuring Time Sundial Clock Measuring Length Examples of Measurement Tools metre rule half-meter rule measuring tape laser measuring device (for measuring the height of high ceilings) Metres (m), Centimetres (cm), millimetres (mm), Kilometres (km) Units Height of a building – measured in "m" Length of a bridge - measured in "km" Diameter of a pencil lead – measured in "mm" We should read the scale from vertically above when measuring the length of an object with a ruler. Alert 14 Jaymee Science S1 Chapter 1 13.2 Measuring Volume Examples of Measuring Cylinder (The curved surface of the liquid in the measuring cylinder Measurement is called "meniscus". Tools or Volume can be found by calculating some Methods objects that have a regular shape. Measure the volume of a Measuring the volume of Measuring the volume of liquid a small irregular object a large irregular object Millilitres (mL), Litres (L), Cubic centimetres (cm3), Cubic metres (m3) Units Alert Our eye should be at the same level as the bottom of the meniscus to take an accurate reading. 15 Jaymee Science S1 Chapter 1 13.3 Measuring Mass Examples of Balance can be used to measure the MASS of an object. Examples are as Measurement follows. Among these examples, "electronic balance" gives the most precise Tools or measurement. Methods *Precision of 0.1g *Precision of 10g *Precision of 0.01g Kilograms (kg), grams (g), milligrams (mg) Units Alert Use "re-zero" (i.e., tare) function of an electronic balance to measure the mass of a substance in a container. 16 Jaymee Science S1 Chapter 1 13.4 Measuring Temperature Examples of Measurement Tools or Methods thermometer coloured alcohol thermometer (used in the laboratory) mercury thermometer (used in the laboratory) temperature sensor connected to a data-logger (precise measurement) wireless sensor Units degrees Celsius (oC) Alert Our eyes should be at the same level as the liquid level in the thermometer. 17 Jaymee Science S1 Chapter 1 13.5 Measuring Time Examples of Stopwatch, watch, clock Measurement Tools or Methods seconds (s), minutes (min), hours (h) Units 13.6 #1: #2: Remarks for measurements We can use electronic instruments for precise measurement. There are errors when we make measurements. Our reaction time to press the start/stop button may be slightly different each time. We have to repeat the measurement several times and calculate an average value in order to reduce errors. The results obtained are more reliable. 14. Transferring and Mixing Solution 14.1 Ways to transfer solutions 18 Jaymee Science S1 Chapter 1 14.2 Four methods for mixing solutions 15. Heating 15.1 In some experiments, a Bunsen burner was used to heat substances. The structure of a Bunsen burner: 15.2 Strike Back: A Bunsen burner may strike back if the air hole is fully open. We will observe a green flame and hear a hissing sound. We have to turn off the gas tap immediately and inform your teacher. Do not touch the chimney and the collar because they are hot. 19 Jaymee Science S1 Chapter 1 15.3 Using a Bunsen Burner 15.4 Observing the Bunsen Flame 20 Jaymee Science S1 Chapter 1 15.5 Observing the Bunsen Flame: Luminous vs. Non-luminous Flame Air hole closed Air hole open Luminous flame Non-luminous flame Colour Yellow Blue Shape Irregular regular Noise Quiet Noisy Temperature Lower Higher Name of the flame 15.6 Heating a liquid by swirling 15.7 Heating a solid 21