Chapter 2 And 4 - Carbon And The Chemical Context Of Life Flashcards
Matter
Anything that takes up space and has mass
Element
A substance that cannot be broken down to other substances by chemical reactions
Compound
A substance consisting of two or more elements combined in a fixed ratio in
Essential Elements
An element that an organism needs to live a healthy life and reproduce
Trace elements
Elements required by elements in only minute qualities
Atom
The smallest unit of matter that still retains the properties of an element
Atomic Nucleus
Where protons and neutrons are packed at the centre of an atom. Protons give the nucleus a positive charge
Electrons around nucleus
The rapidly moving electrons form a “cloud” of negative charge around the nucleus, and it is the attraction between opposite charges that keeps the nucleus electrons in the vicinity of the nucleus
Atomic Number
Number of protons
Mass number
Sum of neutrons and protons in the nucleus of an atom
Isotopes
Different atomic forms of the same element
Radioactive isotope
An isotope whose nucleus decays spontaneously, giving off particles and energy
Energy
That capacity to cause change by doing work
Potential energy
The energy that matter processes because of its location or structure
Valence Electron
Electrons in the outermost shell
Chemical Bonds
Attractions that hold atoms together
Covalent Bonds
The sharing of a pair of valence electrons by two atoms