Woodlands Ring Secondary School Secondary Two G3 Science WA2 Practice Flashcards

These vocabulary flashcards cover the key terminology from Chapter 10 (Heat Transfer), Chapter 11 (Chemical Changes), and Chapter 12 (Ecosystems) as per the Woodlands Ring Secondary School Secondary Two G3 Science curriculum.

Temperature

An objective measure of how hot or how cold an object or region is.

Kelvin ($K$)

The S.I. unit of temperature.

Expansion

Generally, an increase in the volume of an object when it gains heat and its temperature increases.

Contraction

Generally, a decrease in the volume of an object when it loses heat and its temperature decreases.

Expansion gaps

Spaces incorporated into railway tracks to provide room for metal to expand in hot weather without buckling.

Bimetallic strip

Two metals joined together that expand and contract at different rates upon the same change in temperature, causing the strip to curve.

Conduction

The process of thermal energy transfer through a medium without the physical movement of the medium, via vibration and collisions of particles.

Convection

The process of thermal energy transfer from one place to another by the physical movement of a medium, appearing in liquids or gases.

Radiation

The process of thermal energy transfer from a hotter body to a cooler body without the need for a medium.

Greenhouse effect

The process where greenhouse gases like carbon dioxide reflect heat back towards Earth, warming the atmosphere.

Global warming

The increase in the Earth's temperature resulting from an increased greenhouse effect, often caused by the burning of fossil fuels.

Physical Change

A change where no new substances are formed, the properties of products remain the same as starting materials, and it is usually temporary and reversible.

Chemical Change

A change where new substances are formed with different properties, often involving a rearrangement of atoms, and is usually permanent.

Reactants

The names of the substances used in a chemical reaction, shown on the left-hand side of a word equation.

Products

The names of the new substances formed in a chemical reaction, shown on the right-hand side of a word equation.

Combustion

A chemical reaction where a substance reacts with oxygen when heated, releasing energy usually in the form of heat and light.

Thermal decomposition

A chemical reaction where a single compound breaks up into two or more simpler substances when it is heated.

Oxidation

A chemical reaction in which a substance gains oxygen, such as the rusting of iron or cellular respiration.

Neutralisation

A chemical reaction that occurs when an acid is mixed with an alkali to form a salt and water.

Test for Hydrogen Gas

Using a lighted splint which will extinguish with a 'pop' sound in the presence of the gas.

Test for Carbon Dioxide Gas

Passing the gas into limewater; a white precipitate (ppt) forms if the gas is present.

pH scale

A scale numbered from 1 to 14 used to measure how acidic or alkaline a solution is ($ext{pH} < 7$ for acids, $ext{pH} = 7$ for neutral, $ext{pH} > 7$ for alkalis).

Universal Indicator

A mixture of dyes that produces different colours at various pH levels to determine the approximate pH value of a solution.

Ocean acidification

The process where carbon dioxide dissolves in seawater to form carbonic acid, affecting marine organisms with calcium carbonate shells.

Non-renewable resources

Finite resources that cannot be replaced once they are used up, such as fossil fuels.

Structural adaptation

A physical feature of an organism's body that helps it to survive or reproduce in its environment.

Behavioural adaptation

The different actions or behaviours of an organism that help it to survive or reproduce.

Buttress roots

A structural adaptation of the Velvet tamarind tree used to provide support and help absorb minerals.

Breathing roots

A structural adaptation of Mangrove trees that helps the plant obtain oxygen in an environment immersed in seawater.