Human Chemistry 1 Flashcards
What is a chemical?
Any substance consisting of matter
What is matter?
Anything that has mass + takes up space
What is NOT a chemical?
(Energy)Light,heat
(Phenomenon) sound, gravity, mementum
Define an Atom:
The smallest unit of matter
Define an Element:
Atoms of a single-type
EX: H, O, C
Ex: 115 total # of elements
Nucleus of an atom:
Dense central core
Inside an atom’s Nucleus is?
Protons (+) and Neutrons (neutral)
Define the Electron Cloud:
Volume of space outside the nucleus of an atom
What is inside the Electron Cloud:
Electrons negative charge
Define Protons:
Positively charged particiles inside nucleus
Define Atomic #
The # of protons in an element
Each element has a different # of?
Protons
Define Neutrons:
Neutral, uncharged particles in the nucleus
Define Atomic Mass:
of protons and neutrons added together
Define Isotope:
Form of an element that had a different # of neutrons
All Isotopes of an element behave?
Behave the SAME chemically but some will have different physical characteristics like radioactivity
Define Electrons:
Negatively charged particles outside the nucleus
Electrons play a KEY role in?
Chemical Bonds and Chemical Reactions
For a Neutral atom the # electrons is equal to?
Equal to the # of Protons
How are Electrons arranged in the Electron Cloud?
Circle the Nucleus in shells that have different energy levels
Each Electron Shell contains?
A specific # of electrons
Define Valence Electrons:
Electrons in an Atom’s OUTER-MOST shell
Why are Valence electrons importanr?
Valence electrons can be shared w/ other atoms and determine the chemical bonding properties of an atom
