Atom & Molecule Basics
This is the smallest unit of a chemical element that maintains the properties of that element.
atom
Adding this to a system increases the kinetic energy of the particles.
thermal energy
Unlike wood or stone, plastic is classified as a human-made material.
synthetic
The module introduction states that the Earth's oceans are swimming in over this many million square kilometers of plastic.
25 million
This is the first step in the recycling process, where plastics are grouped by their Resin Identification Code.
sorting
this term describes a substance made of two or more different types of atoms chemically bonded together.
compound
This state of matter is characterized by particles that are close together but can slide past one another.
liquid
Most plastics are derived from this natural resource found underground.
petroleum
These tiny pieces of plastic, less than 5mm long, result from the breakdown of larger debris and are easily ingested by marine life.
microplastics
To be reused, plastic is often shredded into these small pieces before being melted.
pellets
This specific type of molecule is formed when many smaller molecules (monomers) link together in a long chain.
polymer
When plastic is heated to be recycled, it undergoes this phase change.
melting
This "Crosscutting Concept" is used to explain how the arrangement of atoms in a plastic determines its flexibility or strength.
Structure and Function
This massive collection of debris in the North Pacific is a primary example of the "Anchor Phenomenon."
Great Pacific Garbage Patch
This type of change occurs when plastic is melted and reshaped, as no new chemical bonds are permanently formed.
physical change
Students must develop these to describe the atomic composition of simple molecules.
Models
In a gas, particles move in this way, which is why they expand to fill any container.
randomly
This is a major reason synthetic plastics are a problem for the ocean: they lack the ability to be broken down by bacteria, a property known as being...
non-biodegradable
Researchers on the Cocos (Keeling) Islands found that a large portion of the 414 million pieces of waste were these items used once and thrown away.
single-use plastics
Because not all plastics melt at the same temperature, this property is used to separate them during the recycling process.
melting point
This is the term for a substance that consists of only one type of atom or molecule throughout.
pure substance
This scientific law states that mass is neither created nor destroyed during a chemical reaction or phase change.
Law of Conservation of Mass
One "impact on society" mentioned in the module is that synthetic materials often provide these, which makes them cheaper and more accessible than natural ones.
functional alternatives (or low-cost solutions)
This is the process by which plastic waste travels from inland rivers to the open sea.
runoff
This is the main limitation of recycling: most plastics can only be recycled a few times before their _____ break down.
polymer chains