hydrogen, nitrogen and ammonia Flashcards
list the properties of hydrogen
lightest element
colourless and odourless
more reactive than copper
oxygen and hydrogen will explode when lit
why is there no hydrogen in air
bc its so light it escapes earth’s atmosphere
what is the properties of nitrogen
colourless, odourless, unreactive gas
use for protein and growth
slighly soluble in water
very inreactive
what is the most and second most mamufactured chemical
sulfuric acid and ammonia
what is the characteristic of ammonia
colourless with strong smell
less dense than air
turns red litmus blue
describe the Haber process
- nitrogen is obtained from air and hydrogen is obtained by reacting a natural gas with steam
- gas mixture is compressed. more and more gas is pumped in until the pressure reaches 200 atmospheres
- compressed gas flows to converter
- mixture is cooled and ammonia condense to liquid
- ammonia is stored in a tank as liquid under pressure
what is the equation for ammonia
N2 + 3H2–> 2NH3
why is nitrogen and hydrogen recycled to the converter
bc only 15% of the mixture leaving is ammonia
how do we obtain nitogen to make ammonia and the equation
air is 80% nitrogen so oxygen is removed by burning oxygen
2H2 + o2 –> 2H2O
where is the energy used to make ammonia from
the heat given out in the reaction from oxygen and hydrogen
how is hydrogen obtained for ammonia and their equation
hydrogen is made by reacting natural gas with steam
CH4 + 2H2o –> [catalyst] CO2 + 4H2
or cracking hydrocarbons from petroleum
C2H6 –> [catalyst] Co2 + 4H2
what is the conditions to make ammonia
400 C and 200 atmospheres
why is the temp to make atmosphere not 350 or 450
bc 350 is too slow and 450 wld need very powerful pumps so expensive
what is used as a catalyst for ammonia
iron
what do plants use nitrogen for
making chlorophyll and proteins
what do plants use potassium for
produce proteins and resist disease
what does plants use for phosphorus
helps root grow and crops ripen
what is a fertiliser
any substance added to soil to make it more fertile
what is an example of natural fertiliser
animal manure
what is synthetic fertiliser
fertilisers made in factories
what is the formula for ammonium nitrate
NH4NO3
what is the formula for pottasium sulfate
K2SO4
what is the formula for ammonium phosphate
(NH4)3PO4
what is the formula for ammonia sulfates
(NH4)2SO4
what is the consequences of fertilisers
in rivers: algae bloom
- algae grows and cover water
when they die bacteria feed on them and uses up all oxygen - fish suffocate
water supply: nitrate ions can end up in water
-converted to nitrate ions in body and binds to haemoglobin so less oxygen carried
-cause illness to infants causing skin to be blue
where is sulfur found
element in underground beds
occurs as a compound in many metals ores like lead ore galena
sulfur compound also occur naturally in fossil fuel
what are the 2 ways to extract sulfur
oil and gas
sulfur beds
how do we extract sulfur from oil and gas
obtained from petroleum or natural gas
hydrogen sulfide in methane is separate and reactede with oxygen to give sulfur
2H2S + O2 –> 2S + 2H2O
how is sulfur obtained from sulfur beds
undeground sulfure beds
superheated water is pumped down to melt the sulfur and carry it to the surface
what are the properties of sulfur
brittle yellow solid
molecular and has low mp
insoluble in water
react with metal to form sulfides
what are the 2 different forms of sulfur
rhombic and monoclinic sulfur
what are the uses of sulfur
make sulfuric acid added to rubber to toughen it making drugs, pesticides, dyes, matches and paper cosmetic, shampoo and body lotion added to cement to make sulfur concrete
what is the properties of sulfur dioxide
forms when sulfur is burned in air colourless gas heavier than air with chocking smell acts as a blech when damp or in a solution kills bacteria
what are the uses of sulfur dioxide
make sulfuric acid
bleach wool, silk and wood pulp
food preservatives
stops growth of bacteria and moulds
how is sulfuric acid made
- sulfur is burned in air
- it is mixed with air to from sulfur dioxide - s+0–>SO2
- it is passed over 4 separate beads of catalysts at 450 C
- 2SO2 + O2 2SO3
- sulfur trioxide dissolved in concentrated sulfuric acid to form oleum
- mixed with water to from sulfuric acid - H2) + S03 –> H2SO4
what is used as a catalyst in contact process
pellets of vanadium V oxide
why is the mixture passed over 4 separate bed of catalyst in the contact process
to give reactant to further chances to react
how to increase the yield of sulfuric acid
sulfur trioxide is removed in the last 2 beds of catalysts
increase pressure by less than 2 atmospheres
why is sulfur trioxide dissolved in concentrated acid and not water
it wld form a thick dangerous mist of acid
how is the temperature of sulfur trioxide maintained
pipes of cold water are coiled ard the catalyst beds to carry heat away
the hat makes water boil and steam is used to generate electricity for plant ro heating building
what min temp does the catalyst works at for contact process
above 400
what are the uses of sulfuric acid
fertilisers
paints, pigments and dyestuff
fibres and plastics
soaps and detergents and car batteries
how is dilute sulfuric acid made
adding concentrated acid to water not by added water to acid bc heat wld be produced
what is a dehydrating agent
removes water
true or false: sulfuric acid is not a dehydrating agent
false
what does acid + metal give
salt + hydrogen
what does acid + metal oxide or hydroxide gives
salt + water
