Chemistry SCH3UO-B Raahim ghori
engineering is the primary field of engineering concerned with the development
of aircraft and spacecraft.
engineers design and build machines such as rockets, satellites that are able
to fly into outer space.
engineering first started in march 16, 1926.
engineers create machines that are able to fly inside of the earths
atmosphere.(helicopters, airplanes, jets)
engineers design machines that are able to go into outer space and on to other
Parts of the
crafts and aircrafts need to be lighter in weight to be more fuel efficient
when going long distances into outer space.
Aerospace engineers choose specific elements from the periodic table
which are lighter in weight and last long to create critical parts of the
spacecraft. (engine, thrusters)
elements used 40 years ago
years ago, Aluminum dominated the aerospace industries. It was considered light
weight, had high temp tolerance, and inexpensive.
of an aircraft was made up of Aluminum. The rest was titanium and steel.
temp of an engine can go as high as 2100 Celsius. We needed materials that had
a higher temp resistance and weigh less for better fuel efficiency.
Alloys used in spacecraft today
However, 20% of Aluminum is used in the structure of the spacecraft.
alloys such as Titanium Aluminide (TiAl) and Aluminum Lithium (AlLi) are taking
over the use of Aluminum in aircrafts.
alloys elevate the temp resistance of Aluminum by more then 600 Celsius and are
light weight, so are overall a better material to use for the critical parts of
then other metals
is made of small amounts of carbon and mostly iron.
is lightweight and resistant to oxidation and heat, however it suffers
from low ductility.
based alloys can lead to an increased the thrust-to-weight ratio in the
is corrosion resistant at elevated temperatures over 600 Celsius.
alloy has taken over the use of nickel in spacecraft because it has similar
properties but is lighter in weight.
lithium is the least dense element, these alloys are significantly less dense
alloys contain about 2.45% by weight of lithium.
used for Internal structures
fiber is a very strong yet light weight material used in internal structures.
fibers are the same as carbon fibers.
carbide is also used.
very hard and are used in applications requiring high endurance.
fiber, ceramic fiber, silicon carbide
the construction of the structures inside the spacecraft, light weight and
durable materials such as carbon fiber, ceramic fiber, and silicon carbide are
hardness, low weight, and low density all together, makes them a very good
material to be used in aircrafts and spacecrafts.
carbide can be easily molded into different type of shapes and can withstand a
lot of heat. This makes them a great material to use around the engines and the
thrusters of the spacecrafts.
for use in engine
is the most crucial part of an aircraft. It does the most work and controls
temperature inside the engine can go as high as 2100 Celsius. This is the
reason why new materials are still in demand which can help with the
construction of the engine.
of the melting points of the alloys are below 2100 Celsius so many new
materials are being discovered to this day that can withstand higher
temperature and weigh less.
related to this lens
First Woman in Space: Valentina Tereshkova | Space Facts – Astronomy, the Solar
System & Outer Space | All About Space Magazine.”, 2017. March 21, Space
Facts Astronomy the Solar System Outer Space All About Space Magazine, www.spaceanswers.com/space-exploration/the-first-woman-in-space-valentina-tereshkova/
Bob, 1 Apr. 2015, “Careers in Aerospace Technology.” NASA, www.nasa.gov/centers/langley/news/factsheets/FS-2001-09-68-LaRC.html.
2 May 2006, “Review of Alloy and Process Development of TiAl Alloys.”
Chemical reactions-part 2:
What are chemical reactions?
u “Chemical reaction, a process in
which one or more substances, the reactants, are converted to one or more
different substances, the products. Substances are either chemical elements or
compounds. A chemical reaction rearranges the constituent atoms of the
reactants to create different substances as products.”-( John C. Kotz,Paul M.
Newtons 3rd law
u Rockets would not be able to fly
without chemistry. Newtons 3rd law is used to power the rockets and
push them out of the earths atmosphere.
u Newtons 3rd law: “For every action, there is an
equal and opposite reaction.” When the chemical reactions occurs and the
pressure of the gases caused by the reactions pushes out of the bottom end of
the rocket, this allows the rocket to launch into the air and out of the
u The chemical reaction that creates
the pressure in the gases in also known as combustion reaction.
u Combustion is a chemical process in which
a substance reacts rapidly with oxygen to give off heat and energy.
u There are two types of combustion. (Complete
combustion, Incomplete combustion)
u The substance that burns in the
reaction is called Fuel. The substance that is the source of oxygen is
called the Oxidizer.
u Fuel: A material used to produce heat or
energy by burning the material.
u Liquid rocket fuel is commonly liquid
oxygen or either kerosene or liquid hydrogen.
u Solid rocket fuel is easier to handle and
is more economically friendly.
u Solid fuel is usually Made from
powdered aluminium and an oxidiser.
What is an oxidizer
u An oxidizer is a type of
chemical which a fuel requires to burn. On earth, oxygen is usually used as an
oxidizer, there is a large amount of oxygen available on earth. But in space,
there is no atmosphere to provide oxygen or other oxidizers. Rockets carry
there own oxidizers which help in the burning of fuel. The are carried in a
separate tank and are released whenever fuel is required to burn to produce
u hydrogen peroxide and the halogens are commonly used as oxidizers in
u Aluminum powder is used as the fuel
in SLS boosters and Aluminum perchlorate is the oxidizer.
u Aluminum is a very reactive element
which is why it is usually found combined with other elements.(as taught in
class and read from textbook)
u Aluminum wants to react and combine
with other elements to become stable which is why it is very useful in the
u Ammonium perchlorate is a compound
with a molecular formula of NH?ClO?. It is a white solid that is soluble in
water. Perchlorate is a powerful oxidizer and ammonium is a good fuel.
u When this substance is burnt,
aluminum is combined with the oxygen being released from ammonium perchlorate
to get a product of aluminum oxide, aluminum chloride, nitrogen gas, water
vapour, and most importantly lots of energy is released.
u This energy uses the newtons 3rd
law to push the rocket out of the earths atmosphere.
How do oxidizers work?
u The combustion reaction takes place
inside the rocket boosters which create temperatures as high as 2800 Celsius.
This causes the particles of nitrogen and water vapour to vibrate quickly which
leads to them expanding rapidly.
u The expanding gases create enough
pressure to lift the rocket and launch it into the outer space.
u The boosters are then disconnected
from the SLS when the rocket is in space to make the overall weight of the
Examples of chemical reactions
u C82H18+17O2à 8CO2+18H2O
Causes of Combustion
u After the reaction, the fuel and the
oxidizer is converted into exhaust and energy.
u To start the process of combustion,
heat is compulsory. Heat is also a product of combustion. This means once the
combustion reaction has started, there is no more need to provide heat
separately because the heat being produced from the reaction will keep the
reaction going. ( as mentioned
u There must be a fuel to burn and a
source of oxygen and also a source of heat to ignite the reaction
u Products of this reaction are water,
heat and energy
The Fuel of Choice for Space Exploration
u Liquid hydrogen is the fuel of choice
for space exploration.
u Hydrogen has the lowest molecular
weight of all elements.(1.00794 u)
u Hydrogen burns at extreme
temperatures as high as 5,500°F.
u It is the most efficient in relation
to the amount of propellant consumed is the reaction.
u Liquid hydrogen must be stored under
extremely low temperatures such as -250 Celsius and must be handle with care to
keep it from evaporating or boiling.
u Liquid hydrogen is used instead of
its gas form because liquids are denser then gases and are easier to handle.
Liquid hydrogen can fit in a lighter/smaller tank than its gas form.
Oxygen reacting with hydrogen
u Oxygen is also compressed into a
liquid form and is cooled and held in temperatures as low as -180 degree Celsius.
u Liquid form of hydrogen and oxygen
evaporate very easily so they require extra care.
u When the liquid hydrogen in ignited,
liquid oxygen reacts with the hydrogen and produce water, heat and energy.
u These elements react explosively
which causes the pressure to push the rocket into space.
What pushes the rocket?
u The combustion reaction between
hydrogen and oxygen produces water vapour and high amounts of energy.
u The water vapour in high temperatures
is also known to us as steam.
u Steam expands due to high
temperatures at speeds of 16000km/hr.
u The pressure caused by the steam
causes the rocket to lift off the ground and into space by escaping the pull of
u This is based on newtons 3rd
law ” For every action, there is an equal and opposite reaction.”
Is it environmentally friendly?
u This reaction is considered a “green”
u The products of this reaction are
water vapour which is also known as steam, and lots of energy.
u The steam is not bad for the
environment and is a very safe way to produce energy.
u Launching rockets using hydrogen and
oxygen is very environmentally friendly.
General thrust equation
u Thrust is a force acting against the force
of gravity and overcome the drag of the rocket.
u To calculate thrust you need to Know:
u Mass flow rate (m)
u Exit velocity (V)
u Exit pressure (Pe)
u Free steam pressure (Po)
u Area (A)
u Equation: F=meVe-moVo+(Pe- Po)Ae
Careers related to this lens
u Chemical engineer
u Manufacturing Engineer
u Aerospace systems engineer
u Space flight engineer
u Flight mechanics
u Dunbar, B. (n.d.).NASA, December 21,
2017, AFOSR Test Environmentally-Friendly Rocket Propellant. January 14, 2018,
u Kotz, J. C., & Treichel, P. M.
(2017, December 13). Chemical reaction. Retrieved January 14, 2018, from https://www.britannica.com/science/chemical-reaction
u Dunbar, B. (n.d.), January 14, 2018
Liquid Hydrogen–the Fuel of Choice for Space Exploration., from https://www.nasa.gov/topics/technology/hydrogen/hydrogen_fuel_of_choice.html
u Hall, C. (n.d.), January 01, 2018,
“Combustion” from https://www.grc.nasa.gov/www/k-12/airplane/combst1.html
u Khan. (n.d.). What is Newton’s third
law? (article). Retrieved January 14, 2018, from https://www.khanacademy.org/science/physics/forces-newtons-laws/newtons-laws-of-motion/a/what-is-newtons-third-law
u Government of Canada, Canadian Centre
for Occupational Health and Safety. (2018, January 12). Oxidizing Liquids &
Solids – Hazards : OSH Answers. Retrieved January 14, 2018, from
Gases in rocket
fuel is made of gases which are compressed to change there state from gas to
gases require special care and should be held under severally low temperatures
as low as -252 Celsius or 20.28Kelvin.
and oxygen are compressed and stored in two different tanks due to the high
must be a right amount of oxygen reacting with hydrogen to fully react. This is
calculated in moles.
Charles law Boyles
When the pressure of the gas is held constant, the volume
increases as the temperature of the gas increases.
When the temperature of a gas is held constant, the volume
increases as the pressure of the gas increases.
When the volume is held constant, the pressure of the gas
increases as the temperature rises.
Combined gas law
combined gas law combines all three gas laws which include Charles law, Boyle’s
law, and Gay-Lussac’s law. It states that the ratio of the pressure of the
product and volume and the temperature of
gas is equal to a constant.
Avogadro’s law mentions,
“equal volumes of all ideal gases, at the same temperature and
pressure, contain the same number of molecules.”
Ideal Gas Law
Ideal gas law
is also known as the general gas equation. It is the equation of the state of a
hypothetical gas also known as the ideal gas. It is a good estimate if the
behavior of most gases under certain conditions.
How do these laws relate to aerospace?
use changes in pressure, temperature, and volume to create enough thrust to
propel the rocket out of the earths atmosphere.
high temperature of the gases due to the combustions reaction between hydrogen
and oxygen result is a rapid expanding in the water vapour molecules which is
the product of the reaction.
rapid expanding is kept in a constant volume which results in even higher
amounts of pressure. This causes the steam to be released and enough thrust is
created to launch the rocket into space.
connects to the Gay-Lussac’s law because the change in
temperature causes the change in pressure as the volume is held constant.(as
taught in class)
is always transferred from one object that has a higher temperature to the
other which has a lower temperature.
shows the amount of heat added/unit temp rise.
is measure in:
Gases used in rockets
is compressed into its liquid form and kept at low temperatures to avoid
evaporating and boiling of the gas. The better the quality of the oxidizer, the
better the performance of the rocket.
Hydrogen is also compressed into its liquid for and kept at extremely low
temperatures. Hydrogen peroxide is a mixture of fuel plus oxidant, whose
combustion takes place which produces lots f pressure and explosive amounts of
energy. Its very light weight which means less weight on the rocket therefore
is easier to carry.
Densities of rocket propellants
0xygen(l) (o2) = 1.14
Nitrogen Tetroxide(N2O4)= 1.45 g/ml
Hydrogen (l) (H2)= 1.11 g/mL
calculate density of a gas?
is equal to mass/volume.
of the gas doesn’t change the density so choose your own volume. (preferable to
choose 1L as the volume) (as taught in class)
New technology for rockets
“If one can figure out how to effectively reuse rockets just like
airplanes, the cost of access to space will be reduced by as much as a factor
of a hundred. A fully reusable vehicle has never been done before. That
really is the fundamental breakthrough needed to revolutionize access to
technology of rockets are also known as reusable rockets.
rockets are launched into air like any other rockets, but they can return back
to land on the launch pad.
reusable rocket will reduce the cost of access to space.
majority of the cost comes from building the rocket which flies only once. With
the reusable rocket, we can explore more about the space by building more
reusable rockets and sending multiple of them into space for new discoveries.
Jobs in this field
propulsion systems engineer
station fuel manager
station systems engineer
Editors of Encyclopædia Britannica. (2016, October 26). Avogadro’s law. from https://www.britannica.com/science/Avogadros-l
E., Wagner, J., Lawrick, E., Moore, K., Anderson, M., Soderlund, L., &
Brizee, A. Welcome to the Purdue OWL. Retrieved from https://owl.english.purdue.edu/owl/resource/560/01/
A. J. (2016, July & aug.). Gay-Lussac’s gas law. Retrieved January 16,
2018, from http://chemistry.bd.psu.edu/jircitano/gases.html
Wall. (2017, April 10). SpaceX Rocket Could Be 100-Percent Reusable by 2018,
Elon Musk Says. Retrieved January 16, 2018, from https://www.space.com/g00/36412-spacex-completely-reusable-rocket-elon-musk.html?i10c.encReferrer=aHR0cHM6Ly93d3cuZ29vZ2xlLmNhLw%3D%3D&i10c.ua=1
N. (n.d.). (Dec, 20, 2017) Combined Gas Law: Definition, Formula & Example,
C. (n.d.). The Ideal Gas Law. Retrieved January 16, 2018, from http://www.science.uwaterloo.ca/~cchieh/cact/c120/idealgas.html
A. (2017, April 24). How to Liquefy Hydrogen. Retrieved January 16, 2018, from https://sciencing.com/liquefy-hydrogen-5220130.html