Module 2 Definitions Flashcards
What are isotopes?
Atoms of the same element (same number of protons and electrons) with different numbers of neutrons and different masses.
What is relative isotopic mass?
The mass of an atom of an isotope compared with 1/12 of the mass of an atom of Carbon-12.
What is relative atomic mass?
The weighted mean mass of an atom of an element compared with 1/12 of the mass of an atom of Carbon-12.
What is an atomic orbital?
A region around the nucleus that can hold up to two electrons, with opposite spins.
What does anhydrous mean?
When all the waters of crystallisation have been removed from a compound.
What does hydrated mean?
When water of crystallisation is present in a crystal compound.
What is water of crystallisation?
The water present in a compound giving the compound a crystalline appearance.
What is the equation for percentage yield?
Percentage (%) Yield = Actual mass of product / Theoretical mass of product x 100
What is the equation for atom economy?
Atom Economy = Molecular mass of desired product / Molecular mass of ALL products x 100
What is an acid?
Proton (H+) donor.
What is a base?
Proton (H+) acceptor.
What is an alkali?
A soluble base that dissolves in water to release OH- ions in aqueous solution.
What is oxidation?
The loss of electrons / increase in oxidation number (state).
What is reduction?
The gain of electrons / decrease in oxidation number (state).
What is an oxidising agent?
A reagent which oxidises another species (and is reduced itself) by gaining electrons.
What is a reducing agent?
A reagent which reduces another species (and is oxidised itself) by losing electrons.
What is a redox reaction?
A reaction where both oxidation and reduction takes place.
What is disproportionation?
A reaction in which the same element is both oxidised and reduced.
What is a metallic bond?
Strong electrostatic attraction between positively charged ions (cations) and delocalised electrons.
What is an ionic bond?
Strong electrostatic attraction between positive and negatively (oppositely) charged ions.
What is a covalent bond?
Electrostatic attraction between a shared pair of electrons and the nuclei of the bonded atoms.
What is a dative (co-ordinate) covalent bond?
The strong electrostatic attraction between a shared pair of electrons and the nuclei of the bonded atoms, where only one of the atoms supplies both the electrons shared.
What is electronegativity?
The ability of an atom to attract the bonding electrons towards itself in a covalent bond.
Why is Mg classed as a s block elements?
An s-block element has its highest energy electron in a s subshell.
This answer can be applied to elements in other blocks too!
What is first ionisation energy?
The energy required to remove one electron from each atom in one mole of gaseous atoms to form one mole of gaseous 1+ ions.
What is metallic bonding?
Strong electrostatic attraction between positively charged ions (cations) and delocalised electrons.
