things to learn Flashcards
nitrate
NO3-
carbonate
CO32-
sulphate
SO42-
hydroxide
OH-
ammonium
NH4+
zinc
Zn2+
silver
Ag+
hydrochloric acid
HCl
sulphuric acid
H2SO4
nitric acid
HNO3
ethanoic acid
CH3COOH
sodium hydroxide
NaOH
potassium hydroxide
KOH
ammonia
NH3
metal + acid –>
salt + hydrogen
metal oxide + acid –>
salt + water
metal hydroxide + acid –>
salt + water
metal carbonate + acid –>
salt + water + carbon dioxide
for a group 2 metal:
2M + O2 –>
2MO
for a group two metal:
M + 2H2O –>
M(OH)2 + H2
MO + H2O –>
M(OH)2
two disproportiantion reactions
Cl2 + H2O –> HCl + HClO
Cl2 + 2NaOH = NaCl + NaClO + H2O
for alkanes and alcohols:
what are the products in complete combustion
CO2 and water
for alkanes and alcohols:
what are the products of incomplete combustion
CO and water
rules for assigning oxidation states
123FHOC
what is Ca(OH)2 used for
neutralise acids in soil
what is Mg(OH)2 and CaCO3 used for
treating indigestion
why can’t covelent compounds conduct electricity
no ions or mobile electrons
what causes a permanent dipole
difference in electronegativity
hydrogen bonding occurs in?
H + any NOF
why do ionisation energies increase across a period
as there are more protons so there is a greater nuclear charge but no extra shielding so electrons are more strongly attracted, so it takes more energy to remove it
for ionisation energies why is there a small decrease from 2nd to 3rd element in the period?
some shielding for the electron in the p subshell by the s subshell
for ionisation energies why is there a small decrease from the 5th to 6th element?
the 6th electron is in an orbital with an electron and there is repulsion between these two electrons
why do ionisation energies decrease down a group?
there are more protons but there are more electron shells too, so more shielding and the electrons are further from the nucleus so they are less strongly attracted and easier to remove
why do group 1 and 2 metals get more reactive down the group?
there are more protons but there are more electron shells too, so more shielding and the electrons are further from the nucleus so they are less strongly attracted and easier to remove
why do group 7 elements get less reactive down the group?
there are more protons but there are more electron shells too, so more shielding and the electrons are further from the nucleus so they are less strongly attracted and its harder to gain electrons
why do successive ionisation energies increase each time?
becuase one electron has already been removed so a smaller number of electrons are left with a greater attraction to the same number of protons. this means the electrons are pulled closer to the nucleus, the atomic radius decreases and its harder to remove the next electron.
why are there sometimes large jumps in successive ionisation energies?
when an electron is being removed from a new shell, it will be closer to the nucleus so there will be more attraction, thus harder to remove
what is the trend in melting points across a period?
increase for the first four and low for the next four
explain the trend in melting point point across a period
the metallic bonds increase as the charge of the ions and the number of electrons increase. the first non metals have giant covalent structures and have high melting points, the rest are simple covalent so have weak IDD interactions holding them together
good thing and bad thing about chlorine in the water
good: kills bacteria in water so reduce waterborne illness
bad: chlorine gas is toxic, can react with organic matter to form carcinogenic compounds
in dynamic equilibrium:
when u increase the concentration of the reactant
equilibrium shifts to the other side (more product produced)
in dynamic equilibrium:
when u increase temperature
equilibrium shifts to the endothermic side
in dynamic equilibrium:
when u increase pressure
equilibrium shifts to the side with the least moles of gas
in dynamic equilibrium:
when a catalyst is used
position of equilibrium doesn’t change but equilibrium is reached quicker
