Chemical Industry

Question 1

how can you follow rate of reaction?

Answer 1

ph
gas vol
loss of mass
colour change
titration

Question 2

initial rate =

Answer 2

amount of reactant used or formed / time

Question 3

how do you do the initial rate method?

Answer 3

time how long it takes for specific vol of gas to form then repeat using different concentrations of one reactant

Question 4

iodine clock reaction equation is…

Answer 4

H2O2 + 2I- + 2H+ —> 2H2O + I2

Question 5

what is the rate equation?

Answer 5

rate = k [A]^m x [B]^n

Question 6

the bigger the rate constant…

Answer 6

the faster the reaction

Question 7

how does a zero order reactant affect rate?

Answer 7

changing concentration has no effect on rate

Question 8

how does a first order reactant affect rate?

Answer 8

if the concentration increases, rate increases proportionally

e.g. if conc doubles, rate doubles

Question 9

how does a second order reactant affect rate?

Answer 9

if the concentration increases, rate increases proportionally squared

e.g. if conc doubles, rate quadruples

Question 10

what is half life?

Answer 10

the half life of a reaction is the time it takes for half the reactant to be used up

Question 11

as a reaction goes on the half life of a zero order reactant…

Answer 11

decreases as the reaction goes on

Question 12

as a reaction goes on the half life of a first order reactant…

Answer 12

remains constant

Question 13

as a reaction goes on the half life of a second order reactant…

Answer 13

increases as it goes on

Question 14

you can find rate constant from….

Answer 14

half life and first order

Question 15

does changing temperature affect rate constant?

Answer 15

yes

Question 16

a calculated rate constant is only valid at…

Answer 16

a certain temperature

Question 17

at a higher temperature rate constant…

Answer 17

will be higher

Question 18

the arrhenius equation links…

Answer 18

rate constant and activation energy

Question 19

what is the arrhenius equation?

Answer 19

k = (-Ea)/RT

Question 20

what is the equation for equilibrium constant?

aA + bB —> dD + eE

Answer 20

Kc = [D]^d x [E]^e / [A]^a x [B]^b

Question 21

if temperature is increased @ equilibrium

Answer 21

eqm shifts in the endothermic direction

Question 22

if temperature is decreased @ equilibrium

Answer 22

eqm shifts in exothermic direction

Question 23

if the increase in temperature means product yield increases…

Answer 23

Kc will increase

Question 24

if the increase in temperature means product yield decreases…

Answer 24

Kc will decrease

Question 25

do pressure changes affect Kc?

Answer 25

no

Question 26

do catalysts have affect on Kc?

Answer 26

no

Question 27

colorimetry and ph readings can be used to…

Answer 27

find equilibrium concentrations

Question 28

what kind of molecule is a nitrogen?

Answer 28

diatomic molecule

Question 29

how many electrons are in nitrogen’s outer shell?

Answer 29

5

Question 30

what is the electron configuration of nitrogen?

Answer 30

1s2 2s2 2p3

Question 31

how do N atoms get a full shell?

Answer 31

they pair up and share 3 pairs of electrons between them

Question 32

nitrogen atoms pair up and share..

Answer 32

3 pairs of electrons between them

Question 33

nitrogen atoms pair up to form a…

Answer 33

triple bond

Question 34

why is nitrogen unreactive

Answer 34

contains a triple bond that is hard to break

Question 35

nitrogen forms three oxides that are…

Answer 35

1. NO 2. N2O 3. NO2

Question 36

NO is called…

Answer 36

nitrogen monoxide

Question 37

NO (nitrogen monoxide) is a _____ gas

Answer 37

colourless

Question 38

N2O is called….

Answer 38

nitrous oxide

Question 39

nitrous oxide smells….

Answer 39

sweet

Question 40

nitrous oxide is a _____ gas

Answer 40

colourless

Question 41

NO2 is called…

Answer 41

nitrogen dioxide

Question 42

NO2 (nitrogen dioxide) is ____ and ____

Answer 42

brown and toxic

Question 43

NO2 (nitrogen dioxide) has a ___ ____

Answer 43

sharp odour

Question 44

ammonias formula is…

Answer 44

NH3

Question 45

N atoms form _____ bonds by sharing _ electron with each ____ . Leaving a ____ ____ on the nitrogen.

Answer 45

1. covalent 2. one 3. hydrogen 4. lone pair

Question 46

why is ammomia soluble in water?

Answer 46

it can form hydrogen bonds with water

Question 47

why can ammonia form dative covalent bonds?

Answer 47

it has a lone pair of electrons

Question 48

the lone pair on the ammonia allows it to act as a…

Answer 48

base

Question 49

what is the test for NH4+ ions?

Answer 49

1. add NaOH to solution and heat 2. if present they react with OH- ions and NH3 is produced 3. red litmus turns blue

Question 50

nitrates react with ammonia in the presence of…

Answer 50

alkali

Question 51

the formula for nitrate ions is

Answer 51

NO3-

Question 52

how do you test for nitrate (v) ions?

Answer 52

1. warm solution with NaOH and aluminium foil (or Devarda’s alloy) 2. if present ammonia gas will be produced 3. so damp red litmus turns blue

Question 53

which oxide containing nitrogen is brown and toxic?

Answer 53

nitrogen dioxide (NO2)

Question 54

which oxide containing nitrogen has a sharp odour?

Answer 54

nitrogen dioxide (NO2)

Question 55

which oxides containing nitrogen are colourless gases?

Answer 55

nitrogen monoxide (NO) and nitrous oxide (N2O)

Question 56

which gas containing nitrogen smells sweet?

Answer 56

nitrous oxide (N2O)

Question 57

if Ea increases k will…. this means the rate will….

Answer 57

get smaller slow down

Question 58

when temperature increases k will…

Answer 58

increase

Question 59

what is seen when nitrogen monoxide gas reaches the atmosphere?

Answer 59

colourless gas turns brown