Element
any substance that cannot be broken down to any other substance by chemical reactions
compound
two or more elements combined in a fixed ratio
define organized matter having emergent properties
a compound has characteristics different from those of its elements
what is the percent of essential elements
20%-25%
Essential elements
a chemical element that an organism needs to survive
4 elements needed make up 96% of living matter.
C,H,O,N
trace elements
an element indispensable for life but required in a small amount
atom
smallest unit of matter that retains the properties of an element
Subatomic particles
atom has part made out of smaller particles
neutrons
a subatomic particle that has no charge
protons
a subatomic particle that has a positive charge
electrons
a subatomic particle that has a negative charge
atomic nucleus
atom's dense center core, containing protons and neutrons
atomic number
the number of protons in the nucleus of an atom
mass number
the sum of protons and neutrons
isotope
element with different number of neutrons
radioactive isotope
isotope that is unstable; nucleus decays spontaneous which gives off particles and energy.
energy
the capacity to cause change
potential energy
the energy that matter possess as a result of its location
Element
any substance that cannot be broken down to any other substance by chemical reactions
compound
two or more elements combined in a fixed ratio
define organized matter having emergent properties
a compound has characteristics different from those of its elements
what is the percent of essential elements
20%-25%
Essential elements
a chemical element that an organism needs to survive
4 elements needed make up 96% of living matter.
C,H,O,N
trace elements
an element indispensable for life but required in a small amount
atom
smallest unit of matter that retains the properties of an element
Subatomic particles
atom has part made out of smaller particles
neutrons
a subatomic particle that has no charge
protons
a subatomic particle that has a positive charge
electrons
a subatomic particle that has a negative charge
atomic nucleus
atom's dense center core, containing protons and neutrons
atomic number
the number of protons in the nucleus of an atom
mass number
the sum of protons and neutrons
isotope
element with different number of neutrons
radioactive isotope
isotope that is unstable; nucleus decays spontaneous which gives off particles and energy.
energy
the capacity to cause change
potential energy
the energy that matter possess as a result of its location