past paper stuff Flashcards
how do London forces arise ???
- uneven distribution of electrons
- creates instantaneous (temporary) dipole
- dipole is induced
what is the name given to repeating pattern of properties along a period ?
periodicity
what to remember with all calculations ?
does it ask for sig figs / decimal places ??
what does xH2O represent ?
water of crystallisation
what is a salt ?
metal /ammonium ion replaces H+ ion in an acid
define dative covalent bond
both electrons donated from same atom
define isotope
atoms of an element with same no of protons, diff no of neutrons
why do isotopes have similar chemical properties ?
same no. of electrons in outer shell
what to remember when drawing H bonds
lone pairs on Oxygen
what are conditions needed to make bleach ?
cold dilute NaOH
what is the 2nd product of metal + water/acid ?
hydrogen
what is meant by ionic lattice ?
repeating pattern of oppositely charged ions
pV =
nRT
what are the units of pressure in pV =
Pa
what are the units of volume in pV =
m3
what are the units of temp in pV =
kelvin
what is R in pV=
8.314 J / K / mol
what does roman numerals show
oxidation number
state two methods of carbon capture and storage
- react with metal oxide to for metal carbonate
- deep in ocean
what are (2) factors of greenhouse effect of a gas ?
- abundance
- ability to absorb IR
to be soluble in water, molecule must be able to …
form H-bonds with water
what is the oxidation of alcohols observation ?
orange to green