C7 Last Minute Flashcards
what is solubility
Solubility: the maximum amount of solute that can dissolve in a given amount of solvent at a given temperature
what does the solubility curve show
• Solubility curve shows the relationship between solubility and temperature.
what happens if solubility increases with temperature vs vice versa
o Solubility increases as temperature increases (positive gradient)
o Solubility decreases as temperature increases (negative gradient)
what is an unsaturated solution vs saturated
- Unsaturated solution: contains less than the maximum amount of solute dissolved at a given temperature
- Saturated solution: contains the maximum amount of solute dissolved at a given temperature
what is a supersaturated solution
contains more dissolved solute than a saturated solution at a given temperature (above the solubility curve)
what is the solubility equation
solubility = mass of solute/volume of solvent
what is volumetric analysis
Volumetric analysis determines the concentration of a solution by measuring the volume of the solution that will react with a known volume of a standard solution via titration.
what is a titration
process of adding a standard solution to a fixed volume of the other solution until the reaction between the two solutions is complete (end point)
what marks the end of titrations and what kind of reactions involve titrations
e.g. acid-base titration, redox titration
o The end point is marked by a colour change of the indicator.
o The equivalence point is reached when the reactants have just reacted
according to the stoichiometric ratio given by the balanced equation.
what is limiting reactant
the reactant that is used up first in a reaction
what is excess reactant
the reactant that is not completely used up
what is the total produce produced in a reaction determined by
The amount of product formed is determined by the limiting reactant.
what are the three concentration equations
conc in g/dm3 = mass of solute/solution vol
conc in mol/dm3 = no. of moles of solute/solution volume in dm3
conc in mol/dm3 = conc in g/dm3/ molar mass of solute
what is the octet rule
Octet rule: atoms tend to form bonds with eight electrons in the outer shell (stable octet configuration (for covalent)
what are some compounds of colvaent bonding
CH4 = Methane
NH3 or NH4+ = Ammonia
CO2
H20
what is an exception to solubility rule in small covalent strutcures
normally small cov are soluble in organic solvents and big covs are insoluble in all substances
however, hydrogen chloride HCl ionises in water
what ares exception to electrical conductivity rule for covalent strutcures
Hydrogen chloride (HCl) ionises in water to form acidic solutions with mobile H+ and Cl– ions which conduct electricity
large = graphite can
what do alkali metals react with oxygen to make
alkali metal OXIDE
What happens down list of alkali metals
softness increase
density increase
reactivity increase
melting boiling point decrease
what do alkali metals react with water to make
ALKALI METAL HYDROXIDE + Hydrogen H2
what do halogens do
displacement
what are trends of halogen down a group
colour darker
melting point boiling point increase
reactivity decrease
gas to solid
how can we separate solid from liquid
insoluble solid = filter or decantation
soluble solid = evaporation to dryness/distillation/crystallisation
how can we separate immisicible liquids and what is an example
separating funnel
oil + water (immiscible means they cant mix)
how can we separate misicible liquids and what is an example
fractional distillation
how can we separate solids and what is an example
evaporation to dryness/distillation/crystallisation/dissolving
what is chromatography used for
Used to separate and identify small amounts of substances that are dissolved in solvents
what is the principle of solubility
substances are separated because of differences in solubilities in a particular solvent
what is chromatography equation
distance travelled by substance/distance travelled by solvent
what are acid reactions with other substances
Acid + metal = hydrogen + salt
acid + base = water + salt
acid + carbonate = water + salt + carbon dioxide
what are strong acids vs weak
strong: H. S. N
weak: E, P, C
what are strong alkalis vs alkalis
strong: NaOH/KOH/Ca(OH)2
weak: NH4+
what does a force-extension staright line mean and then curve
limit of proprtionality is whne teh staright line of a force-extenson graph becomes a curve
what happens if elastic goes past l.o.p
becomes inelastic and deformed
what makes a spring stiffer
higher spring constant
what is newtons first law
A body will remain at rest or in a state of uniform motion in a straight line unless acted on by a resultant external force.
car will be still or acceleration will be zero unless force acts on it
what is newtons second law
force = mass x acceleration
what is newtons third law
If body A exerts a force on body B then body B exerts an equal and opposite force of the same type on body A.
• Forces always occur in pairs called action and reaction forces.
what are forces always done in
action forces and reaction forces
in netwons third law, what is each force done in
- equal in magnitude Mass and Weight Mass - opposite in direction - acting on different bodies - of the same nature
