C7 Last Minute

Question 1

what is solubility

Answer 1

Solubility: the maximum amount of solute that can dissolve in a given amount of solvent at a given temperature

Question 2

what does the solubility curve show

Answer 2

• Solubility curve shows the relationship between solubility and temperature.

Question 3

what happens if solubility increases with temperature vs vice versa

Answer 3

o Solubility increases as temperature increases (positive gradient)
o Solubility decreases as temperature increases (negative gradient)

Question 4

what is an unsaturated solution vs saturated

Answer 4

• 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

Question 5

what is a supersaturated solution

Answer 5

contains more dissolved solute than a saturated solution at a given temperature (above the solubility curve)

Question 6

what is the solubility equation

Answer 6

solubility = mass of solute/volume of solvent

Question 7

what is volumetric analysis

Answer 7

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.

Question 8

what is a titration

Answer 8

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)

Question 9

what marks the end of titrations and what kind of reactions involve titrations

Answer 9

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.

Question 10

what is limiting reactant

Answer 10

the reactant that is used up first in a reaction

Question 11

what is excess reactant

Answer 11

the reactant that is not completely used up

Question 12

what is the total produce produced in a reaction determined by

Answer 12

The amount of product formed is determined by the limiting reactant.

Question 13

what are the three concentration equations

Answer 13

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

Question 14

what is the octet rule

Answer 14

Octet rule: atoms tend to form bonds with eight electrons in the outer shell (stable octet configuration (for covalent)

Question 15

what are some compounds of colvaent bonding

Answer 15

CH4 = Methane
NH3 or NH4+ = Ammonia
CO2
H20

Question 16

what is an exception to solubility rule in small covalent strutcures

Answer 16

normally small cov are soluble in organic solvents and big covs are insoluble in all substances

however, hydrogen chloride HCl ionises in water

Question 17

what ares exception to electrical conductivity rule for covalent strutcures

Answer 17

Hydrogen chloride (HCl) ionises in water to form acidic solutions with mobile H+ and Cl– ions which conduct electricity

large = graphite can

Question 18

what do alkali metals react with oxygen to make

Answer 18

alkali metal OXIDE

Question 19

What happens down list of alkali metals

Answer 19

softness increase
density increase
reactivity increase

melting boiling point decrease

Question 20

what do alkali metals react with water to make

Answer 20

ALKALI METAL HYDROXIDE + Hydrogen H2

Question 21

what do halogens do

Answer 21

displacement

Question 22

what are trends of halogen down a group

Answer 22

colour darker
melting point boiling point increase
reactivity decrease
gas to solid

Question 23

how can we separate solid from liquid

Answer 23

insoluble solid = filter or decantation

soluble solid = evaporation to dryness/distillation/crystallisation

Question 24

how can we separate immisicible liquids and what is an example

Answer 24

separating funnel

oil + water (immiscible means they cant mix)

Question 25

how can we separate misicible liquids and what is an example

Answer 25

fractional distillation

Question 26

how can we separate solids and what is an example

Answer 26

evaporation to dryness/distillation/crystallisation/dissolving

Question 27

what is chromatography used for

Answer 27

Used to separate and identify small amounts of substances that are dissolved in solvents

Question 28

what is the principle of solubility

Answer 28

substances are separated because of differences in solubilities in a particular solvent

Question 29

what is chromatography equation

Answer 29

distance travelled by substance/distance travelled by solvent

Question 30

what are acid reactions with other substances

Answer 30

Acid + metal = hydrogen + salt acid + base = water + salt acid + carbonate = water + salt + carbon dioxide

Question 31

what are strong acids vs weak

Answer 31

strong: H. S. N weak: E, P, C

Question 32

what are strong alkalis vs alkalis

Answer 32

strong: NaOH/KOH/Ca(OH)2 weak: NH4+

Question 33

what does a force-extension staright line mean and then curve

Answer 33

limit of proprtionality is whne teh staright line of a force-extenson graph becomes a curve

Question 34

what happens if elastic goes past l.o.p

Answer 34

becomes inelastic and deformed

Question 35

what makes a spring stiffer

Answer 35

higher spring constant

Question 36

what is newtons first law

Answer 36

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

Question 37

what is newtons second law

Answer 37

force = mass x acceleration

Question 38

what is newtons third law

Answer 38

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.

Question 39

what are forces always done in

Answer 39

action forces and reaction forces

Question 40

in netwons third law, what is each force done in

Answer 40

``` - equal in magnitude Mass and Weight Mass - opposite in direction - acting on different bodies - of the same nature ```