Lower Secondary Basic Science - Workbook 1

Chapter 1: Skills, Processes, and Procedures

Introduction to Science

• Science is described as both knowledge and a process involving experiments to find answers to problems.

• Major branches of science defined include:

  • Biology: The study of living things.

  • Chemistry: The study of chemicals and how to change them.

  • Physics: The study of energy, matter, and movement.

  • Astronomy: The study of planets, stars, and the universe.

  • Geology: The study of rocks and the Earth.

  • Ecology: The study of how plants and animals interact together in the environment.

Safety in the Science Room

• General Rules:

  1. Only enter with a teacher; wear lab coats and closed, flat footwear.

  2. No running or pushing on slippery, hard floors.

  3. Keep notebooks tidy and away from experiments.

  4. No food, lollies, gum, or drinking from laboratory glassware.

  5. Do not taste or inhale chemicals; wash hands after lab work.

  6. Liquid waste goes in sinks/waste bottles; solids in bins; broken glass in special bins.

  7. Clean equipment and work benches after use.

• Heating and Mixing Rules:

  8. Never look inside a flask/beaker being heated; do not point the open end of containers toward yourself or others. Wear safety goggles.

  9. Always use the correct method for lighting a Bunsen burner.

  10. Let equipment cool before handling.

  11. Tie back long hair.

  12. Keep flammable substances away from naked flames.

• Protocol for Accidents:

  13. Report all breakages and damage immediately.

  14. Spilled acids/chemicals on skin should be washed with ample running tap water.

  15. Smother clothing fires with a blanket or coat; never run.

Hazardous Material Labels

• Poison: Example: Chloroform.

• Flammable: Example: Methylated spirit.

• Corrosive: Example: Caustic soda, concentrated hydrochloric acid.

• Explosive/Combustible Hazard: Example: Sodium in water.

Laboratory Equipment and Apparatus

• Microscopes:

  • Simple Microscope: Uses one magnifying lens in a tube.

  • Compound Microscope: Uses two lenses (eyepiece and objectives) to magnify small objects using light.

  • Stereo/Dissecting Microscope: Used for thicker objects and observing tissues/organs during dissection.

  • Care Instructions: Carry with two hands (one on base, one on arm); use special tissue paper for lenses; store in a dustproof cover.

• Bunsen Burner:

  • Invented by Robert Bunsen in 1855.

  • Safety Flame: Yellow, produced when the air hole is closed. Not used for heating.

  • Heating Flame: Pale blue, produced when the air hole is open to mix air with gas.

• Common Apparatus and Uses:

  • Test Tube: Holding/mixing small volumes.

  • Test Tube Holder: Holding hot test tubes.

  • Beaker: Holding/heating large volumes of water.

  • Tripod Stand: Supporting objects above a burner.

  • Gauze Wire: Supporting objects above a tripod.

  • Conical Flask: Heating/storing liquids; wider base for greater surface area.

  • Measuring Cylinder: Measuring large liquid volumes ($mL$).

  • Triple Beam Balance: Finding mass.

  • Spring Balance: Measuring weight using gravity/spring force.

  • Thermometer: Taking temperature in $^\circ C$ or $^\circ F$.

  • Watch Glass: Evaporating liquids or holding small samples.

Measurement and Data

• Metric System: The standard system in Fiji.

• Prefixes:

  • Mega ($M$): Multiply by $1\,000\,000$.

  • Kilo ($k$): Multiply by $1\,000$.

  • Centi ($c$): Multiply by $1/100$.

  • Milli ($m$): Multiply by $1/1000$.

  • Micro ($\mu$): Multiply by $1/1\,000\,000$.

• Reading Volume: Always read from the bottom of the meniscus (the curve water forms against glass).

• Graphing Formulas: To convert portion percentages into degrees for a pie chart: $3.6^\circ \times X\% = Y^\circ$.

Scientific Method and Investigating

• Observation: Noticing things using the five senses.

• Inference: A likely explanation for an observation.

• Hypothesis: A testable guess at an answer.

• Variable: Factors that can be changed or measured. Only one variable should be changed at a time in a fair test.

• Control: A standard for comparison used to ensure a fair test.

Chapter 2: Matter

Structure and Properties of Matter

• Definition: Anything that has mass and takes up space.

• Particle Theory: All matter is made of particles in constant motion.

• States of Matter:

  • Solids: Particles in fixed patterns, vibrate only, fixed volume/shape.

  • Liquids: More energy, space between particles allows flow, fixed volume but no fixed shape.

  • Gases: Loosely held particles, high energy, move freely to fill any container.

Atomic Structure Models

• Dalton (1807): Hard, dense sphere.

• Thomson (1903): Electrons scattered throughout.

• Rutherford (1911): Dense nucleus with protons and neutrons, surrounded by orbiting electrons.

• Atomic Number ($Z$): Number of protons; determines the element.

• Mass Number: Total protons plus total neutrons.

• Electrical Neutrality: Protons ($+$) must equal electrons ($-$).

Expansion and Contraction

• Heating causes particles to gain energy and move further apart (expansion).

• Cooling causes particles to lose energy and move closer (contraction).

• Real-world Applications:

  • Bridges: Gaps and rollers allow for expansion.

  • Railway lines: Gaps prevent buckling in heat.

  • Power lines: Hung loosely to avoid snapping during cold-weather contraction.

Materials and Chemical Content

• Natural Materials: Wood (trees), Metals (ores), Cotton (plants), Leather (animal skins).

• Synthetic Materials: Plastics (crude oil), Glass (sand/limestone), Alloys (metal mixtures), Ceramics (clay).

• Water Types:

  • Hard Water: Contains calcium/magnesium salts; does not lather easily with soap; forms scum.

  • Soft Water: Lathers easily; contains few minerals.

• Detergents vs. Soaps: Detergents (petroleum-based) lather in hard water but are often non-biodegradable and can be toxic if swallowed. Soaps (vegetable oil-based) are biodegradable.

Chemical Reactions

• Element: Pure substance with one type of atom (e.g., $Fe$, $O$, $N$).

• Ion: Formed when an atom loses electrons (Cation, positive) or gains electrons (Anion, negative).

• Acids: pH < 7; taste sour; turn blue litmus red. Examples: Hydrochloric acid ($HCl$), Sulphuric acid ($H_2SO_4$).

• Bases/Alkalis: pH > 7; taste bitter; feel soapy; turn red litmus blue. Examples: Sodium hydroxide ($NaOH$), Magnesium hydroxide ($Mg(OH)_2$).

• Neutralization: Acid + Base $\rightarrow$ Salt + Water.

• Gas Tests:

  • Hydrogen: Identified by a "pop" sound with a burning splint.

  • Carbon Dioxide: Turns limewater milky ($white\,precipitate$).

Chapter 3: Living Things and the Environment

Life Processes and Ecology

• MRS GREN: Movement, Respiration, Sensitivity, Growth, Reproduction, Excretion, Nutrition.

• Ecosystem Components: Energy, chemicals, producers, and consumers.

• Symbiosis Types:

  • Mutualism: Both species benefit.

  • Commensalism: One benefits, the other is unaffected.

  • Parasitism: One benefits (parasite), the other is harmed (host).

Coral Reefs

• Corals are colonial animals made of polyps.

• Zooxanthellae: Algae living in corals that assist in reef building.

• Types of Reefs: Fringing (common in Fiji), Lagoon, Barrier, and Platform.

• Coral Examples: Staghorn Coral (Lasetagane), Brain Coral (Vatubuso), Fire Coral (Lasekata).

Plant Science

• Anatomy: Internal structure study.

• Morphology: External structure study.

• Plant Responses (Tropisms):

  • Phototropism: Growth toward light.

  • Geotropism: Response to gravity.

  • Hydrotropism: Response to water levels.

  • Thigmotropism: Response to touch (climbing plants).

• Photosynthesis Equation:     $\text{Carbon\,Dioxide} + \text{Water} + \text{Light} \rightarrow \text{Sugars} + \text{Oxygen}$

• Transpiration: Evaporation of water from leaves through stomata. Factors increasing rate: Light, temperature, low humidity, and wind.

Biodiversity and Conservation in Fiji

• Invasive Species: African Tulip (forests), American Iguana (disrupts food security on Qamea/Taveuni).

• Conservation Groups: World Wildlife Fund (WWF), BirdLife Fiji (Natewa Peninsula), NatureFiji (Mareqeti Viti).

Chapter 4: Energy

Energy Sources

• Sun: The principal energy source.

• Renewable: Solar, Wind, Hydro (e.g., Monasavu), Geothermal (e.g., Savusavu Hot Spring), OTEC (Ocean Thermal Energy Conversion), Tidal, Wave.

• Non-renewable: Coal, oil, gas, and uranium.

• Coal Formation Stages: Peat $\rightarrow$ Brown Coal (Lignite) $\rightarrow$ Black Coal (Bituminous) $\rightarrow$ Anthracite $\rightarrow$ Graphite.

Forms of Energy

• Mechanical: Energy of motion/position; Kinetic ($KE$) or Potential ($PE$).

• Chemical: Stored in bonds of food, fuel, or matches.

• Thermal: Internal motion of atoms; measured as temperature.

• Electromagnetic: Travels in waves (Light, X-rays, Radio).

• Nuclear: Energy from the nucleus; Fission (splitting) or Fusion (joining, like the Sun).

Light and Reflection

• Properties: Travels in straight lines; does not require a medium.

• Material Interaction:

  • Transparent: Transmits almost all light.

  • Translucent: Scatters light; shapes are fuzzy.

  • Opaque: Absorbs or reflects all light; forms shadows.

• Reflection Law: Angle of incidence equals angle of reflection.

• Mirrors:

  • Plane: Virtual image, same size as object.

  • Concave: Caves inward; used in car headlights and dentists' mirrors.

  • Convex: Bulges out; provides a wide view for security/car mirrors.

Forces

• Friction: Opposes movement. Reduced by lubricants, streamlining, or ball bearings.

• Gravity: Attraction to the Earth's center. Weight is the force of gravity measured in Newtons ($N$); Mass is the amount of matter in kilograms ($kg$).

• Weight on Moon: Approx. $1/6$ of weight on Earth due to lower mass.

Chapter 5: Earth and Beyond

The Solar System

• Sun: Contains $99.8\%$ of the solar system's mass.

• Planets:

  • Terrestrial (Inner): Mercury, Venus (hottest, greenhouse effect), Earth, Mars (Red planet, Olympus Mons volcano).

  • Gas Giants (Outer): Jupiter (largest, Great Red Spot), Saturn (rings), Uranus (blue-green), Neptune (Great Dark Spot).

  • Dwarf Planet: Pluto (downgraded in 2006).

• Mnemonic: "My Very Energetic Mother Just Served Us Noodles."

The Moon and Tides

• Phases: Occur because different amounts of the sunlit part are visible from Earth.

• Spring Tides: Extra large; occur when Sun, Moon, and Earth align.

• Neap Tides: Weak; occur when they are at right angles.

Eclipses

• Solar Eclipse: Moon passes between Sun and Earth; daytime phenomenon.

• Lunar Eclipse: Earth passes between Sun and Moon; Moon turns reddish-orange in the umbra (full shadow).

Traditional Fijian Seasons (Vula)

• January (Vula I Nuqa Levu): Abundance of Rabbit fish.

• February (Vula I Sevu): First crops (Dalo, Uvi).

• May (Vula I Doi): Doi trees flower; Mackerel (Salala) abound.

• July (Vula I Cukicuki): Octopus season starts.

• August (Vula I Seni drala): Drala trees flower; Kawakawa breeding.

• November (Vula I Balolo Levu): Harvesting of Balolo edible sea worms; Walu fish abound.

Climate Change Impacts

• Global Warming: Gradual increase in Earth's average surface temperature.

• In Fiji: Salt intrusion in groundwater; coral bleaching; increased vector-borne diseases like Dengue and water-borne diseases like Leptospirosis.

• Greenhouse Gases: Carbon dioxide (burning fuel), Methane (livestock), CFCs (refrigerants), Nitrous oxides (fertilizers).