Science Task 4 - Materials and Environmental Sustainability

What are the 5 criteria required for a substance to be classified as a mineral?

• Naturally Occurring

• Inorganic

• Solid

• Definite chemical composition

• Crystalline internal structure

What is the difference between a Group and a Period on the Periodic Table?

Group (Column): Tells you the number of valence electrons; elements share similar chemical properties.

Period (Row): Tells you the number of electron shells an atom has.

What is the difference between an Ionic bond and a Covalent bond?

Ionic: Formed between a metal and non-metal via the transfer of electrons (creating positive cations and negative anions).

Covalent: Formed between non-metals by sharing pairs of electrons.

What is the general formula and definition for an Alkane?

Definition: A saturated hydrocarbon containing only single carbon-carbon bonds. Cn H{2n+2}

What are the products of Complete combustion?

Complete (excess O2): Carbon Dioxide CO2 + Water H2O

What are the products of incomplete combustion?

Incomplete (limited O2): Carbon Monoxide CO + Carbon (soot) + Water H2O

What is Fractional Distillation used for?

Separating crude oil into different hydrocarbon fractions based on their different boiling points (hotter at the base, cooler at the top).

What is a Polymer and a Monomer?

Monomer: A small, repeating chemical unit.

Polymer: A large molecule made by joining many monomers together (e.g., plastics, starch).

What is Environmental Sustainability?

Meeting the needs of current generations without compromising the ability of future generations to meet their own needs (protecting natural resources and biodiversity).

What is the difference between Weather and Climate?

• Weather: Short-term atmospheric conditions over minutes to days (e.g., rainy today).

• Climate: Long-term average weather patterns observed over 30+ years.

What is the Enhanced Greenhouse Effect?

Human activities (like burning fossil fuels and deforestation) increase greenhouse gas concentrations (CO2, methane), trapping excess heat and driving global warming.

What is a Positive Feedback Loop in climate science?

A self-reinforcing cycle where an initial change triggers consequences that amplify that change (e.g., rising temperatures, melting ice, lower reflection/albedo, more heat absorbed).

What are Earth's Four Spheres?

• Atmosphere (gases/air)

• Hydrosphere (water)

• Lithosphere / Geosphere (solid earth/rocks)

• Biosphere (living organisms)

What is Bioaccumulation?

The gradual build-up of toxic chemicals or microplastics inside living organisms over time because they cannot be easily broken down or excreted.

What are the components of an atom and where are they located?

• Nucleus (Center): Contains Protons (+) and Neutrons (0).

• Electron Shells (Surrounding): Contains Orbiting Electrons (-).

What are the step-by-step rules for drawing a Bohr electron shell diagram?

• Draw a central circle for the nucleus, writing the number of protons (p) and neutrons (n) inside.

• Draw concentric rings for shells.

• Fill shells using maximum capacity rules: Shell 1 = max 2, Shell 2 = max 8, Shell 3 = max 8

What information is found in a standard Periodic Table box for an element?

• Atomic Number (Top - number of protons)

• Chemical Symbol (Center - 1 or 2 letter abbreviation)

• Element Name (Below symbol)

• Atomic Mass / Mass Number (Bottom - protons + neutrons)

How do you find the number of electrons in a neutral atom?

Look at the Atomic Number. In a neutral atom, Electrons = Protons = Atomic Number.

What is "Electron Configuration" and what is Aluminium's configuration?

• Definition: The arrangement of electrons into shells from the inside out.

• Aluminium (Atomic Number 13): 2, 8, 3

What is the definition of the Valence Shell?

The outermost electron shell of an atom, furthest from the nucleus.

What is a Stable Configuration?

A full outer electron shell (usually 8 valence electrons, matching a noble gas), making the atom unreactive and chemically stable.

What is Valency?

The number of chemical bonds an atom can form, determined by how many electrons it needs to gain, lose, or share to become stable.

What is an Ion, a Cation, and an Anion?

• Ion: An atom or molecule with an overall electrical charge due to gained/lost electrons.

• Cation (+): A positively charged ion formed when a metal atom loses electrons.

• Anion (-): A negatively charged ion formed when a non-metal atom gains electrons.

What are the three main types of chemical bonds and how do they form?

• Ionic Bond: Transfer of electrons between a metal and a non-metal (forming ions).

• Covalent Bond: Sharing of electron pairs between non-metals.

• Metallic Bond: Positive metal ions surrounded by a delocalised "sea" of free valence electrons.

Give a real-world example for each type of chemical bond (Ionic, Covalent, Metallic)

• Ionic: Sodium Chloride (NaCl - Table salt)

• Covalent: Water (H2O) or Carbon Dioxide (CO2)

• Metallic: Pure Copper (Cu) or Iron (Fe)

What is a Diatomic Molecule? Give examples.

• Definition: A molecule made up of exactly two atoms chemically bonded together.

• Examples: Oxygen (O2), Hydrogen (H2), Chlorine (Cl2).

What is the difference between Physical and Chemical properties?

• Physical: Characteristics observed without changing the substance's chemical identity (e.g., melting point, color, state).

• Chemical: Characteristics describing how a substance reacts to form new substances (e.g., flammability, reactivity with acid, rusting).

What are the 3 Core Goals and Principles of Environmental Sustainability?

Protect natural resources, reverse ecosystem damage and minimse climate change