Test Questions and Answers Graded
A+ 2025/2026 Updated.
Atom - Answer the smallest representative particle of an element that can enter into
chemical combinations
retains its identity during chemical reactions
Proton - Answer a subatomic particle found in the nucleus
has a positive charge equal in magnitude but opposite in sign of an electron
Neutron - Answer a neutral subatomic particle found in the nucleus of an atom
almost identical mass to a proton
Electron - Answer a negatively charged subatomic particle found outside the atomic nucleus
Atomic Number - Answer the number of protons in the nucleus of an atom
Atomic Symbol - Answer a 1 or 2 letter notation used to represent an atom corresponding to
a particular element
Isotope - Answer atoms that have the same number of protons in the nucleus but have
different numbers of neutrons
same *atomic number* but different *atomic mass*
Atomic Mass - Answer the average of the masses of an element's naturally occurring
isotopes weighted according to their abundances
equal to: Σ [ (isotope mass) x (fractional natural abundance) ]
, Avogadro's Number - Answer number of particles (or any objects) in a mol of any substance
equal to *6.022 x 10^23*
Mole - Answer the amount of a substance that contains Avogadro's Number of elementary
entities
Matter - Answer anything that occupies space and has mass
Elements - Answer a substance that cannot be decomposed by chemical means into simpler
substance
type of matter composed by only 1 kind of atom, each atom of a given kind having the same
atomic number and properties
Allotrope - Answer 1 of 2 or more distinct forms of an element in the same phase, differing
in (internal) structure
Molecule - Answer a chemical combination fo 2 or more atoms in a specific arrangement
held together by chemical bonds
smallest particle of a compound that exists independently and retains chemical properties of
that compound
Compound - Answer a substance composed of 2 or more elements chemically combined
(bonded) in fixed proportions
Ions - Answer electrically charged particle resulting from an atom/molecule that has
gained/lost 1 or more electrons, giving it a (+) or (-) charge
Chemical Properties - Answer properties that describe a substance's composition and
reactivity