Reading...
Play button
Play button
Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
20 Cards in this Set
- Front
- Back
|
definition of "element"
|
a substance that cannot be broken down to other substances by chemical reactions. there are 92 recognised elements occurring in natures
|
|
|
definition of "compound"
|
a substance consisting of two or more different elements combined in a fixed ration.
|
|
|
definition of "trace elements"
|
required by an organism in only minute quantities. examples are iron (Fe) and iodine (I).
|
|
|
definition of "atom"
|
the smallest unit of matter that still retains the properties of an element.
|
|
|
definition of "subatomic particles"
|
the tiny bits of matter that compose an atom
|
|
|
what are the three main types of subatomic particles?
|
neutron, proton, and electron
|
|
|
definition of "atomic nucleus"
|
the center of an atom, where protons and neutrons are packed together tightly in a dense core
|
|
|
what is a dalton?
|
a subatomic unit of measurement
|
|
|
definiton of "atomic number"
|
the number of protons, which is unique to each element and is written as a subscript to the left of the symbol for the element.
|
|
|
definition of "mass number"
|
the sum of protons plus neutrons in the nucleus of an atom. written as a superscript to the left of an element's symbol.
|
|
|
definition of "atomic mass"
|
an approximation of the total mass of an atom
|
|
|
definition of "isotope"
|
the different atomic forms of an element, where some atoms have more neutrons than other atoms of the same element and therefore have greater mass.
|
|
|
definition of "radioactive isotope"
|
an isotope in which the nucleus decays spontaneously, giving off particles and energy.
|
|
|
definition of "energy"
|
the capacity to cause change
|
|
|
definition of "potential energy"
|
the nergy that matter possesses because of its location or structure.
|
|
|
definition of "valence electrons"
|
outer electrons; the outermost electron shell is the valence shell
|
|
|
definiton of an "orbital"
|
the sphere where an electron spends 90% of its time
|
|
|
definiton of "single bond"
|
a pair of shared electrons
|
|
|
definition of "ion"
|
a charaged atom (or molecule)
|
|
|
definition of "cation"
|
when an ion's charge is positive
|
