Definitions Flashcards
Matter
Anything that has got mass and occupies space. Examples - A book, water, air, oxygen, carbon dioxide….
Atoms
Atoms are the smallest part of an element and can take part in chemical reactions.
Compound
A substance formed when two or more chemical elements are chemically bonded together.
Element
A substance made entirely from one type of atom.
Quarks
Fundamental types of particles, makes up protons and neutrons.
Isotopes
Two atoms are isotopes of the element if they have the same atomic numbers (number of protons) but they have different mass numbers (different number of electrons and neutrons).
Electronic Configuration
Electronic configuration shows the arrangement of electrons in different shells.
Mass Number
Total number of protons and neutrons in the atoms of that element.
Atomic Number
Number of protons in the atoms of that element. Atoms of one element will always have exactly the same number of protons (i.e. - they have the same atomic number).
Valence Electrons
Electrons on the outermost shell.
Stable Atoms
Atoms where the valence shell is full making them stable.
Ions
An atom that is not stable will either gain or lose electrons so that its outermost shell is full. It does this to attain stability. Once an atom gas gained or lost an electron it is no longer electrically neutral, once an atom has gained or lost an electron it is called an ion.
Periodic table
A table of elements organised in a certain way based on 7 rules. Columns are called groups and rows are periods.
Precipitate
Solid that occurs when a chemical reaction takes place.
Rate of Reaction
Reaction rate is a measure of how fast a reaction is occurring.
