Day 1 Flashcards
What is an atom
Building block
What is an element
Collection of like atoms. Examples: Carbon, hydrogen, gold.
What is a molecule?
Covalently bonded atoms (units of chemicals). Examples include H2O, CH4 (methane), NH3 (Ammonia) but also O2 and H2.
What is a compound?
Compositions of different atoms. There are two types: molecular (covalently bonded “clumps” of molecules) or ionic (ionically bonded “latices”). Examples include H2O, CH4 (methane), NH3 (Ammonia).
Atomic weight
The resulting mass from taking the weighted average for the different existing isotopes for that atom type (note this is a mass, not a weight). (The number given by the periodic table)
Atomic mass
Total mass of protons and neutrons of a given element.
Atomic number
The number of protons in an atom.
Isotope
One of two or more variations of a given element differentiated by the number of neutrons. Think siblings. Examples: carbon-12, carbon-14.
Nucleon
Neutron or proton
Mole
Unit of measurement. 1 mole of any element contains avagadro’s number of constituent components. So 1 mole of carbon contains 6.022 x 10^23 atoms of carbon. 6hundred and 2 hexazillion.
Ion
An atom or molecule with non-zero net charge. This comes from having a different number of protons and electrons.
Reactant
An input in a chemical reaction.
Product
An output in a chemical reaction.
Significance of a mole.
Avagadro’s number is a nice way to convert to a standard measures of mass. This is because it is pretty much based off how many AMUs are in 1 gram. An AMU is pretty much the weight of a nucleon. So there is 1g of mass per mol of AMU.
Elementary particles
The most basic units of matter. The types are leptons, quarks, and force carriers (photons are one). These compose hadrons such as protons and neutrons. Electrons are an elementary particle (lepton).
Molarity
Molar concentration of a chemical species in a solution expressed as mols per liter.
Mass number
The total number of nucleons.
Cation
A positively charged ion.
Nucleus
Positively charged center of atom consisting of protons and neutrons.
Exothermic
Reaction that releases heat.