formulae equations and amounts

Question 1

formulae of sulfuric acid

Answer 1

H2SO4

Question 2

formulae of nitric acid

Answer 2

HNO3

Question 3

formulae of ethanoic acid

Answer 3

CH3COOH

Question 4

acid + metal

Answer 4

salt + hydrogen

Question 5

acid + alkali

Answer 5

salt + water

Question 6

acid + carbonate

Answer 6

salt + carbon dioxide + water

Question 7

acid + oxide

Answer 7

salt + water

Question 8

ammonia + acid

Answer 8

ammonium salt

Question 9

soluble salts

Answer 9

ALL sodium, potassium and ammonium salts
ALL nitrate salts
SOME sulphate salts
SOME chloride salts
sodium, potassium, ammonium carbonates and hydroxides

Question 10

insoluble salts

Answer 10

calcium, barium, lead sulphate
silver and lead chloride
all other carbonates and hydroxides

Question 11

mole definition

Answer 11

amount of a substance that contains the same number of particles found in 12g of C-12

Question 12

avogadro’s constant definition

Answer 12

the number of atoms in exactly 12g of C-12 (6.02x10^23 mol-1)

Question 13

molar mass definition

Answer 13

mass of one mole of the substance expressed in gmol-1

Question 14

empirical formula definition

Answer 14

smallest whole number ratio of atoms of each element in a compound

Question 15

molecular formula definition

Answer 15

the actual number of atoms of each element in a molecule

Question 16

Avogadro’s law

Answer 16

if conditions of temperature and pressure are the same, equal volume of gases contain the same number of molecules

Question 17

precision definition

Answer 17

how close the values obtained in an experiment are to each other

Question 18

accuracy definition

Answer 18

how close the values are to the actual value

Question 19

percentage uncertainty

Answer 19

(uncertainty/reading) x 100

Question 20

percentage yield

Answer 20

(actual yield/theoretical yield) x 100

Question 21

atom economy

Answer 21

(molar mass of desired product/total molar mass of all products) x 100

Question 22

how to write ionic equation

Answer 22

1. write balanced equation
2. add state symbols
3. split aq into individual ions
4. cancel common ions
5. rewrite equation and include state symbols

Question 23

how to work out number of particles present

Answer 23

number of moles of that particle x Avogadro’s constant

Question 24

how to work out a reacting masses question

Answer 24

1. calculate moles of substance you know mass of
2. use molar ration to work out number of moles of unknown
3. calculate mass of substance form moles

Question 25

concentration equation

Answer 25

c = n/v OR c = m/v

Question 26

how to work out limiting reactants

Answer 26

1. work out number of starting moles for each reactant 2. identify limiting using ratio 3. use moles of limiting to work out mass of product that can be made

Question 27

volume of gas equation

Answer 27

number of moles x molar volume (24 at RTP) (dm3mol-1)

Question 28

ideal gas equation

Answer 28

pV = nRT p = pascals (1atm = 101000 Pa) V = m3 (1000dm3) n = moles R = 8.31 Jmol-1K-1 T = K (celcius + 273)

Question 29

how to work out empirical formula

Answer 29

1. work out moles (m/Mr m can be %) 2. find ratio

Question 30

experimental error

Answer 30

((real answer - experiment answer) / real answer) x 100