Unit 1 - Chemistry Flashcards
What is chemistry?
Chemistry is the study of the changes and transformations of matter, and the energy involved
What are chemistry’s fields of study?
Inorganic, Organic, Analytical, Physical, Biochemistry
What does organic chemistry study?
It studies carbon-based compounds, usually containing carbon-hydrogen bonds
What does inorganic chemistry study?
It studies all compounds not studied by organic chemistry
What are physical phenomena?
Phenomena that don’t change a substance’s composition
What are chemical phenomena?
Phenomena that change a substance’s composition
What are physical properties?
Properties that can be measured and observed without a substance changing composition
What are chemical properties?
Properties that are shown when there is a change in chemical structure
What are some examples of physical properties?
Organoleptic (senses), mass, volume, density, boiling and melting point
What are some examples of chemical properties?
Reactivity, chemical bond, pH, flammability, toxicity, heat of combustion
How is matter and its subclasses classified?
Matter - Mixtures and Pure Substances
Mixtures - Homogeneous and Heterogeneous
Pure Substances - Elements and Compounds
What are elements?
They are a pure substance made up of equal atoms that can’t be decomposed into simpler substances
What are compounds?
They are a pure substance made up of the chemical bonding of two or more different atoms that lose their original properties and gain new ones
How can elements be classified?
Metals, non-metals, metalloids
What are mixtures?
They are the physical union of multiple elements or compounds where no chemistry happens
What are the two types of mixtures?
Heterogeneous and homogeneous mixtures
What are heterogeneous mixtures?
Mixtures that aren’t fully uniform
What types of heterogeneous mixtures are there?
Emulsions, suspensions, colloids
What are emulsions?
An heterogeneous mixture that consists of a liquid mixed with another undissolved liquid
What are suspensions?
An heterogeneous mixture that consists of big solid particles dispersed in liquid that eventually sink. 1000+ um
What are colloids?
An heterogeneous mixture that consists of small solid particles dispersed in liquid that don’t sink. <1000 um
What are two unmixable liquids called?
Immiscible liquids
What are homogeneous mixtures?
Mixtures whose components are uniformly distributed. They are also known as solutions
What are solutions’ two components?
Solvent (bigger part), solute
What are the four states of matter?
Solid, liquid, gas, plasma
What are the states of matter dependent on?
Cohesion forces, repulsive forces, ion formation
What states of matter have definite volume?
Solids and liquids
What states of matter have Brownian motion?
Gases and plasmas
What are the characteristics of plasmas?
Indefinite shape and volume, electrically conductive, production of magnetic fields and electric currents
How is a gas converted to a plasma?
By exposing it to high temperatures or applying a huge voltage
What happens to electrons in plasmas?
They are stripped from the atoms’ nucleus
What factors are involved in changes of state?
Heat energy and pressure
What are all the changes of state called?
Solid-Liquid: Melting and Freezing
Liquid-Gas: Vaporization and Condensation
Gas-Plasma: Ionization and Recombination
Solid-Gas: Sublimation and Deposition
In terms of what four qualities did Aristotle describe the composition and behavior of matter?
Hot-Cold, Wet-Dry
What was the first chemical revolution?
It was a reformulation of chemistry that culminated in the law of conservation of mass and oxygen theory of combustion. During the 19th and 20th century this was accredited to french chemist Antoine Lavoisier, the father of modern chemistry
Who proposed phlogiston theory and what did it say?
Georg Ernst Stahl. Phlogiston was the essence of fire. It was an invisible fluid that was released with burning
Who proposed dephlogisticated air and what was it?
Joseph Priestly. He discovered air has a particular gas in which flames burn brighter and in which animals and plants live. He thought it had no phlogiston, hence the name.
What did Henry Cavendish do?
His first publication combined three short chemistry papers on factitious airs or gases produced in the laboratory.
He produced “inflammable air” (hydrogen) by dissolving metals in acid
He produced “fixed air” (carbon dioxide) by dissolving alkalis in acids
How did Henry Cavendish collect the gases he produced?
In bottles inverted over water or mercury
