C5 Flashcards
what does dry air consist of
dry air consists of gases such as oxygen , nitrogen , argon carbon dioxide etc. carbon dioxide is a compound gas , a compound is multiple different types of element bonded together.
what does the air consist of
the air consists of roughly 78% nitrogen 21% oxygen 1% argon 0.04% carbon dioxide
what are molecular substances
molecular substances are substances where atoms within a molecule are held together by strong covalent bonds
what happens in covalent bonding
in covalent bondings electrons are shared
what is a molecular substance
a molecular substance is a substance which contains lots of molecules that are not bonded together there are weak forces of attraction between the molecules however the forces within the molecule which hold it together are strong
when would an atom make a covalent bond
some atoms chose to make covalent bonds in order to attain a full outer shell through sharing electrons atoms are able to fill up their outer shells , they must make enough covalent bonds `(share enough electrons) to have a complete outershell
Most non-metal elements and most compounds of non metal elements are
molecular
the strength of covalent bonds
covalent bonds are strong compared to the weak forces of attraction between small covalently bonded molecules
how do you know how many covalent bonds a covalently boded molecule makes
the number of bods is equal too the number of electrons shared , so oxygen shares two electrons thus makes two covalent bonds
what are the boiling and melting points of ionic compounds like
the boiling points of ionic compounds are very strong as ions with opposite charges are strongly attracted to each other by electrostatic forces of attraction and lots of energy is needed to overcome these strong forces of attraction
the ions in an ionic compound can be identified by
completing a flame test , ionic compounds of some metals produce flames of a distinguishable colour
