EL 7

Question 1

what are the four types of acids which you need to know the name and formulas of

Answer 1

sulfuric acid - H2SO4
nitric acid - HNO3
hydrochloric acid - HCL
ethanoic acid - CH3COOH

Question 2

what are the features of a salt and what is created when an acid and a base reacts

Answer 2

ionic compound
positive ion (cation) is either a metal ion or an ammonium ion
negative ion (anion) comes from the acid
when an acid and base react the acid gives away its H+ ion and the H is replaced by metal cation from alkali/base.
e.g. H2SO4 + Mg —- MgSO4 + H2

Question 3

definition of an acid and a base

Answer 3

acid - proton donor
base - proton acceptors

Question 4

what do the acid and base become after the acid has donated its hydrogen to the base

Answer 4

acid becomes a conjugated base since it can now accept a H+ ion
base becomes a conjugated acid as it has gained a H+ ion that it can now donate

Question 5

what are the three different ways of reacting acids to produce salts

Answer 5

neutralise acids with-
carbonates
bases
alkalis (soluble bases)

Question 6

what are the products of reacting an acid with a carbonate and how can you tell it is a carbonate being reacted

Answer 6

acid + carbonate —- salt + H20 + CO2
e.g. 2HCl + CaCO3 —- CaCl2 + H20 +CO2
if you react a compound with an acid and see bubbles then the compound is a carbonate (CO2 gas being released)

Question 7

what are the products of an acid being reacted with a base

Answer 7

acid + base —- salt + H2O
e.g. 2HCl + CaO —- CaCl2 + H2O

Question 8

what is a diprotic acid

Answer 8

an acid that has 2 replaceable H+ ions (H2SO4)

Question 9

what is electronegativity

Answer 9

an atoms tendency to attract the electrons in a covalent bond

Question 10

what is the solubility of ionic compounds in water

Answer 10

giant ionic lattice dissolves in polar solvents
solvent molecules break down ionic lattice structure by surrounding each ion and making new bonds with it to form a solution

Question 11

what are the solubility rules

Answer 11

all nitrates are soluble
all carbonates are soluble except NH4+ and group 1 elements
most sulphates are soluble except for BaSO4, PbSO4 and SrSO4
all chlorides are soluble except for AgCl and PbCl2
all sodium, potassium and ammonium salts are soluble

Question 12

are all nitrates soluble

Answer 12

yes

Question 13

are carbonates soluble (what are the exceptions)

Answer 13

yes carbonates are soluble
exceptions-
NH4+ and group 1 elements

Question 14

what sulphates aren’t soluble

Answer 14

BaSO4
PbSO4
SrSO4

Question 15

what chlorides aren’t soluble

Answer 15

AgCl
PbCl2

Question 16

what salts are always soluble

Answer 16

potassium, ammonium and sodium

Question 17

trends in solubility in group 2

Answer 17

carbonates in group 2 get less soluble as you go down the group
hydroxides get more soluble as you go down group 2

Question 18

are silver halides soluble

Answer 18

no they are insoluble

Question 19

what hydroxides are soluble

Answer 19

sodium, potassium and ammonium hydroxides are soluble
(most hydroxides are insoluble, except group 1 and NH4+)

Question 20

what is a spectator ion

Answer 20

anything that starts and ends a reaction without changing sate

Question 21

what structure do ionic compounds have

Answer 21

giant ionic lattice

Question 22

how are ionic bonds formed

Answer 22

when electrons are transferred from a metal to a non-metal
ions form ionic bonds with each other due to electrostatic forces of attraction

Question 23

properties of ionic compounds (state, mp/bp, force of attraction)

Answer 23

all solid at room temperature
high melting and boiling points
high amounts of energy needed to break strong electrostatic forces of attraction
larger the charges on the ions the stronger the forces of electrostatic attraction and the more energy needed to break bonds

Question 24

electrostatic conductivity of ionic compounds

Answer 24

conductivity in a solid lattice-
ions are help in a fixed position by electrostatic forces of attraction
ionic compound cannot conduct electricity

conductivity in a melted or dissolved state-
lattice structure breaks down and ions are free to move
ionic compound can conduct electricity

Question 25

features of metallic bonding structure

Answer 25

positive ions have fixed positions in the lattice outer shell electrons are delocalised and shared in the lattice metal is held together by the electrostatic attraction between the positive ions and negative delocalised electrons

Question 26

properties of the giant metallic lattices in metallic bonding

Answer 26

conduct electricity - delocalised electrons are spread throughout the lattice and can move freely so can conduct electricity high melting and boiling point - attraction between positive ions and delocalised electrons is strong so high temperatures required to break the metallic bonds malleable and ductile- metal can be hammered into shape due (malleable) and can be drawn out/stretched (ductile) the delocalised electrons are free to move which allows atoms or layers slide past each other

Question 27

what are the two types of covalent compounds

Answer 27

simple covalent molecular lattice giant covalent molecular lattice

Question 28

properties of simple molecular lattice bonds

Answer 28

atoms are bonded together by strong intramolecular bonds (covalent) intermolecular bonds between molecules are weak (van der Waals)

Question 29

how is a van der Waals force created

Answer 29

electrons in covalent bonds can move around the molecule so instantaneous dipole forms in a molecule which can influence electron distribution in other molecules nearby so they become induced dipoles forms force of attraction between the two molecules (positive end of one and negative end of the other) which is weak (van der Waals forces)

Question 30

when do van der Waals forces occur

Answer 30

only occur in covalent molecules only occur between non-polar molecules

Question 31

what do van der Waals forces allow

Answer 31

allow simple non-polar covalent molecules to be soluble in non-polar substances (induced dipole bonds are formed between the two)

Question 32

when is the van der Waals forces stronger

Answer 32

the more electrons in a molecule the stronger the force of attraction on the temporary dipole will be induces stronger dipole on neighbouring molecules the more electrons you have

Question 33

what are the properties of simple molecular lattices

Answer 33

low melting and boiling points - due to weak van der Waals forces little energy needed to break bonds electrical conductivity - do not conduct electricity as there are no free to move charged particles solubility - soluble in non-polar solvents due to van der Waals forces that forms between molecule and non-polar solvent. weak intermolecular bonds between molecules break and new intermolecular bonds are formed with the solvent

Question 34

what is the solubility of giant covalent lattices

Answer 34

insoluble in both polar and non-polar solvents covalent bonds are too strong to be broken by solvents

Question 35

properties of diamond (structure, conductivity, hardness)

Answer 35

structure- tetrahedral held together by strong covalent bonds throughout the lattice conductivity- does not conduct electricity since it has no delocalised electrons hardness- shape allows forces to be spread throughout lattice

Question 36

properties of graphite (structure, conductivity, hardness)

Answer 36

structure- strong forces within layers weak van der Waals forces between the layers conductivity- can conduct electricity due to delocalised electrons that are free to move between layers hardness- soft since weak intermolecular forces allow sliding of layers