module 2: foundations in chemistry Flashcards
which subatomic particles are found in the nucleus?
protons and neutrons
where are electrons found in an atom?
arranged in shells surrounding the nucleus
what is the relative mass of an electron?
1/1836
what are isotopes?
atoms with the same number of protons and electrons, but with different numbers of neutrons
what is the mass number of an atom?
the number of protons and neutrons
what is the atomic number of an atom?
the number of protons
what is an ion?
a charged atom
what are cations?
positive ions
what are anions?
negative ions
how are ions formed?
when an atom gains or loses electrons
what is meant by the relative atomic mass?
the weighted mean mass of an atom of an element, relative to 1/12th of the mean mass of an atom of carbon-12
what is meant by the relative isotopic mass?
the mass of an atom of an isotope compared with 1/12th of the mass of an atom of carbon-12
what is meant by the relative molecular mass?
the weighted mean mass of a molecule of a compound compared with 1/12th of the mass of an atom of carbon-12
state the similarities and differences between isotopes of the same element
similarities:
- same number of protons
- same number of electrons
differences:
- different number of neutrons
- different mass numbers
why do isotopes have the same chemical properties?
they have the same number of electrons in the outer shell
when does ionic bonding occur?
between a metal and a non-metal
what is the charge on a carbonate ion?
2-
what is the charge on a sulfate ion?
2-
what is the empirical fomula?
the simplest whole number ratio of atoms of each element present in a compound
what is the molecular formula?
shows the number and types of atoms of each element present in a molecule
what is a standard solution?
a solution of known concentration
what is the limiting reagent?
the reactant that is not in excess, which will be used up first and stop the reaction
what is the ideal gas equation?
pV = nRT
what is an acid?
a species that releases H+ ions in aqueous solutions
what is an alkali?
a type of base that dissolves in water forming hydroxide ions
what is a strong acid?
an acid which fully dissociates in aqueous solutions
what is a weak acid?
an acid which partially dissociates in aqueous solutions
what is oxidation?
the loss of electrons
what is reduction?
the gaining of electrons
what is the effect of oxidation and reduction on the oxidation number?
oxidation - increase in oxidation number
reduction - decrease in oxidation number
what is an oxidising agent?
a reagent that accepts electrons from another species
what is disproportionation?
a redox reaction in which the same element is both oxidised and reduced