Chemistry and Biology Review Notes

These flashcards cover fundamental concepts in chemistry and biology, including definitions and key properties related to elements, reactions, cells, climate change, and light.

Element

A pure substance made up of only one type of atom.

Atom

The smallest unit of an element.

Compound

A substance formed from two or more different elements bonded together.

Chemical Reaction

The original substance is changed into a new substance that has different properties.

Physical Change

A change that can be observed through our senses where the particles do not change.

Chemical Change

A change where the properties of new substances are different from the original and the particles change.

Homogeneous Mixture

A mixture that is uniform throughout and contains only one phase.

Heterogeneous Mixture

A mixture with physically separate sections and more than one phase.

Isotope

Atoms of the same element that have different numbers of neutrons.

Atomic Number

The number of protons in an atom.

Atomic Mass

The weighted average masses of all isotopes of an element.

Neutron

A particle with no charge found in the nucleus.

Electron

A negatively charged particle that orbits the nucleus.

Cation

A positively charged ion.

Anion

A negatively charged ion.

Lewis Dot Diagram

A representation showing the valence electrons around an element's symbol.

Valence Electron

The electrons in the outermost energy level of an atom.

Molecule

A group of two or more non-metal atoms bonded together.

Binary Compound

A compound containing two different elements.

Polyatomic Ion

A group of atoms that behave as a single ion.

Acid

A compound that produces hydrogen ions when dissolved in water.

Base

A substance that produces hydroxide ions when dissolved in water.

pH Scale

A measure that indicates the acidity or basicity of a solution, ranging from 0 to 14.

Photosynthesis

The process by which plants convert sunlight into chemical energy.

Cell Theory

The fundamental concept that all living organisms are made of cells, which are the basic units of life.

Prokaryotes

Simple, single-celled organisms that do not have a nucleus.

Eukaryotes

Organisms with cells that contain a nucleus and other organelles.

Chromosome

A thread-like structure made mostly of DNA found in the nucleus.

Stem Cell

A non-specialized cell that can replicate or differentiate into specialized cells.

Climate Change

Long-term alteration of temperature and typical weather patterns in a place.

Greenhouse Gases

Gases that trap heat in the atmosphere, contributing to global warming.

Diatomic Molecule

A molecule consisting of two atoms of the same or different elements.

Chemical Equation

A representation of a chemical reaction that shows the reactants and products.

Balanced Chemical Equation

An equation that has the same number of atoms for each element on both sides.

Electromagnetic Wave

Energy in the form of a wave associated with electric and magnetic fields.

Refractive Index

The ratio of the speed of light in a vacuum to the speed of light in a medium.

Total Internal Reflection

When light is completely reflected back into a medium, occurring when the angle of incidence exceeds the critical angle.