Grade 8 Science Final Exam Review

A comprehensive vocabulary review covering chemistry, biology, physics, mechanics, and environmental science based on the Grade 8 Science Final Exam Review Booklet.

Pure substances

Matter that can be classified as elements or compounds.

Solubility

Refers to how well a solute dissolves in a solvent.

Saturated, unsaturated, and supersaturated

Terms used to describe solutions with varying amounts of dissolved solute.

Density

A property of matter calculated using the formula $Density = Mass \div Volume$.

Buoyancy

The upward force exerted by a fluid, explained by Archimedes’ principle.

Viscosity

A property that describes a fluid’s resistance to flow, where higher viscosity results in slower flow.

Compressibility

A characteristic where gases can be compressed while liquids and solids cannot.

Particle model

A theory explaining that all matter is made of particles with space between them.

Organelles

Structures within a cell, such as the nucleus, mitochondria, and chloroplasts, that perform specific functions.

Levels of organization

The structural hierarchy of living things: Cell \rightarrow Tissue \rightarrow Organ \rightarrow System \rightarrow Organism.

Alveoli

Structures in the lungs where gas exchange occurs.

Capillaries

Vessels that connect arteries and veins and allow for the diffusion of gases and nutrients.

Hemoglobin

The substance used by red blood cells to carry oxygen.

Cell membrane

The part of the cell that controls what enters and leaves.

Reflection

A phenomenon where the angle of incidence equals the angle of reflection, such as in a plane mirror.

Refraction

The bending of light as it moves through different media like lenses or water.

Convex lenses

Lenses that converge light; used in magnifying glasses to enlarge images.

Concave lenses

Lenses that diverge light.

Translucent

Materials that let some light through but scatter it.

Opaque

Materials that block all light.

Transparent

Materials that let light pass through clearly.

Dispersion

The process of splitting light into colours using a prism.

Work

Calculated as $Work = Force \times Distance$ and measured in joules ($J$).

Mechanical Advantage ($MA$)

The ratio of force multiplication calculated as $Load \div Effort$.

Speed Ratio

The ratio calculated as $Input Distance \div Output Distance$.

Efficiency

The measurement of a machine's performance, calculated as $(Output Work \div Input Work) \times 100\%$.

Inclined planes

Simple machines that reduce effort but increase the distance over which force is applied.

Watershed

An area of land that drains water to a common point, such as the Athabasca draining into the Arctic Ocean.

Estuaries

Nutrient-rich areas where salt water and fresh water mix.

Desalination

The process used to remove salt from seawater.