Basic of cars and chemistry related to it.

2. Topics
• Engines
• Fuels
• Battery
• Paints
• Pollution
• Future

3. Engine
Engines are made up of the following basic parts
-the engine block & cylinder head
-Cylinders
-Crankshaft
-connecting rods
-pistons
-spark plugs
-fuel injector
-intake and exhaust valves
-camshafts
-timing chain

4. The Four “Strokes”

5. The Four “Strokes”
• Intake stroke - Air and vaporized fuel are drawn
in.
• Compression stroke - Fuel vapor and air are
compressed and ignited.
• Power stroke - Fuel combusts and piston is
pushed downwards.
• Exhaust stroke - Exhaust is driven out.

6. Batteries
• Automotive batteries are mostly of Lead-Acid batteries.
• Total six galvanic cells each of 2.1Volt to provide 12.6volts at full charge.
• Lead-acid batteries are made up of plates of lead and separate plates of lead
dioxide, which are submerged into an electrolyte solution of about 38% sulfuric
acid and 62% water.[

7. pollution
Pollutant How it is formed
carbon monoxide
incomplete combustion of the
fuel in car engines
oxides of nitrogen
formed from the heat and
pressure found in a car engine
sulphur dioxide
sulphur impurities in the fuel
burn

8. Catalytic convertors
• Car exhaust systems have catalytic converters. These convert carbon monoxide to
carbon dioxide:
• carbon monoxide + nitrogen monoxide → nitrogen + carbon dioxide
• 2CO + 2NO → N2 + 2CO2
• Transition metal catalysts can convert the pollutant gases to harmless gases.
Catalytic converters usually have a honeycomb shape to increase the surface area
for reaction with the gases. The catalysts are platinum or rhodium.

9. How can we make cleaner engines?
• There's no doubt that Otto's gasoline engine was an invention of genius—but it's
now a victim of its own success. With around a billion cars on the planet, the
pollution produced by vehicles is a serious—and still growing—problem. The
carbon dioxide released when fuels are burned is also a major cause of global
warming. The solution could be electric cars that get their energy from cleaner
sources of power or hybrid cars that use a combination of electricity and gasoline
power.

10. Fuels
Petrol and diesel are the two major type of fuels
used in automobiles
1.Petrol(Gasoline):
92% iso octane & 8% heptane : 92octane
gasoline
The two different types of antioxidants used in
gasoline are phenylenediamines (PDA) and
hindered phenols (such as BHT).
They act as antioxidants,metal
deactivators, and detergents.
Typical formula for Gasoline is
C8H18.
Combustion Reaction of Gasoline:
2 C8H18 + 25 O2 → 16 CO2 + 18 H2O+Heat energy

11. 2:Diesel
Diesel is composed of about 75% saturated hydrocarbons (primarily paraffins
including n, iso, and cycloparaffins), and 25% aromatic hydrocarbons (including
naphthalenes and alkyl benzenes). The average chemical formula for common
diesel fuel is C12H23, ranging from approx. C10H20 to C15H28. Petrol consists of
hydrocarbons with between 5 and 12 carbon atoms per molecule but then it is
blended for various uses. Overall a typical petrol sample is predominantly a
mixture of paraffins (alkanes), naphthenes (cycloalkanes), aromatics and olefins
(alkenes). The ratios vary based on a variety of factors.

12. What is a hybrid?
•Hybrid electric vehicles (HEVs) include both a combustion engine as well as an
electric motor.
•If we had better batteries, we would not need hybrids at all.
•Hybrids can be implemented in many kinds of vehicles.

13. Why hybrids?
•Regenerative braking actually makes city driving more economical than on the
highway.
•Fuel efficiency is greatly increased (twice).
•Emissions are greatly decreased.
•Dependency on fossils fuels can be decreased.
•Hybrids can be run on alternative fuels as well.
•New materials can be implemented.

14. What exactly is a Hydrogen Car!
In a hydrogen car, its primary source of power is from breaking down hydrogen
The use of hydrogen usually happens by two methods
Hydrogen can be burned much like the combustion reaction that takes place in the gas
powered cars seen today. This is called a internal hydrogen combustion engine
OR
Hydrogen can be set up to react with oxygen to produce water and electricity. This is
called a fuel cell.

15. Advantages
Zero emissions (pure water is produced)
No dependence on foreign oil
Ability to harvest solar and renewable energy
Not many moving parts in a vehicle (more mileage before things start breaking)
Hydrogen weighs less than gasoline (vehicles would not need as much energy to move)
Zero

16. Price Tag: Drawbacks to Hydrogen Car
Hydrogen Supply
At this time there are very few stations that supply hydrogen cylinders to power a car
Also, the price for hydrogen is comparable to gas; however it takes two or three times
as much to power a car.
As of now it is very expensive to equip a car with a hydrogen fuel cell.
Hydrogen is expensive to make, store, and transport
As of now, in a fuel cell the center is a platinum plate which is very expensive

17. Comparable Efficiencies
Hydrogen Fuel cells at over 50% efficiency
Fossil fuel powered car at 10% - 20% efficiency
Hybrid powered cars have 30% - 35% efficiency
Ethanol is less efficient than fossil fuel
- ethanol gets 20% less mpg than fossil fuels

18. Chemistry In Airbags!!
Timing is everything in an airbag's ability to deploy
quickly enough to save a life in a head-on collision.
An airbag must be able to deploy in a matter of
milliseconds from the initial collision impact, and
also be prevented from deploying when there is no
head-on collision (airbags will not deploy in side or
rear impact collisions). Thus, the main component
of the airbag system is a sensor that can detect
head-on collisions and immediately trigger the
airbag's deployment. The crash sensor is a steel ball
that slides inside a smooth bore. The ball is held in
place by a permanent magnet or by a stiff spring,
which inhibit the ball's motion when the car drives
over bumps or potholes. However, when the car
decelerates very quickly, as in a head-on crash, the
ball suddenly moves forward and turns on an
electrical circuit, initiating the process of inflating
the airbag.

19. How airbags works!
Once the electrical circuit has been turned
on by the sensor, a pellet of sodium azide
(NaN3) is ignited. A rapid reaction occurs,
generating nitrogen gas (N2). This gas fills a
nylon or polyamide bag at a velocity of 150
to 250 miles per hour. This process, from
the initial impact of the crash to full
inflation of the airbag, takes only about 40
milliseconds. Ideally, the body of the driver
(or passenger) should hit the airbag just
after inflation – in fact while the airbag
begins to deflate. Otherwise, the high
internal pressure of the airbag would
create a surface as hard as stone.

20. Chemical Reactions(In Airbags)-
Inside the airbag is a gas generator
containing a mixture of NaN3, KNO3, and
SiO2. When the car undergoes a head-on
collision, a series of three chemical
reactions inside the gas generator produce
gas (N2) to fill the airbag and convert NaN3,
which is highly toxic, to harmless glass.
Sodium azide (NaN3) can decompose at
300oC to produce sodium metal (Na) and
nitrogen gas (N2). The signal from the
deceleration sensor ignites the gas-
generator mixture by an electrical impulse,
creating the high-temperature condition
necessary for NaN3 to decompose. The
nitrogen gas that is generated then fills the
airbag.

21. Chemical Reactions(In Airbags)-
The purpose of the KNO3 and SiO2 is to
remove the sodium metal (which is highly
reactive and potentially explosive, by
converting it to a harmless material. First,
the sodium reacts with potassium nitrate
(KNO3) to produce potassium oxide (K2O),
sodium oxide (Na2O), and additional N2
gas. The N2 generated in this second
reaction also fills the airbag, and the metal
oxides react with silicon dioxide (SiO2) in a
final reaction to produce silicate glass,
which is harmless and stable. (First-period
metal oxides, such as Na2O and K2O, are
highly reactive, so it would be unsafe to
allow them to be the end product of the
airbag detonation.)

22. Reaction 1:
2NaN3  2Na + 3N2
Reaction 2:
10Na + 2KNO3  K2O
+ 5Na2O + N2
Reaction 3:
K2O + Na2O + SiO2 
Na2K2SiO4 (alkaline silicate glass)

23. An Airbag System In a typical car!

25. Automotive Paint
Automotive paint is paint used
on automobiles.
It consists of 3 coats—
1. Primer
2. Basecoat
3. Clear coat

26. Primer
The primer is the first coat to be
applied.
The main functions of the primer
are to act as a leveller and
protector, and to make the base
coat easier to apply to the
component to which it is applied.

27. Functions of Primer in brief-
1. As a leveller: this is important since
the cab often has marks and other
forms of surface defect after being
manufactured in the body shop. A
smoother surface is created by levelling
out these defects and therefore a better
final product.
2. As a protector: the primer will
protect from corrosion, heat
differences, bumps, stone-chips, UV-
light etc.
3. Ease of application: by making it
easier for paints to stick to the surface a
more varied range of paints can be
used.

28. Basecoat
The base coat is applied after the
primer coat.
This coat contains the visual
properties of colour and effects,
and is usually the one referred to
as the paint.
Base coat used in the automotive
applications is commonly divided
into three categories, solid,
metallic, pearlescent colours.

29. Basecoat
The solid paints has no sparkle effects
except the colour. This is the easiest type
of paint to apply, and the most common
type of paint for heavy transportation
vehicles, construction equipment and
aircraft. It is also widely used on cars,
trucks, and motorcycles.

30. Basecoat
The metallic paints contains
aluminium flakes to create a
sparkling and grainy effect, or as
people generally refer as a
metallic look. This paint is harder
to manage than the solid paints
because of the extra dimensions
to consider. Metallic and pearl
paints must be applied evenly to
ensure a consistent looking finish
without light and dark spots
which are often called
"mottling".

31. Basecoat
Pearlescent Paints contain
special iridescent pigments
commonly referred to as
"pearls". Pearl pigments impart a
colored sparkle to the finish
which works to create depth of
color. Pearlescent paints can be
two stage in nature (pearl base
color + clear) or 3 stage in nature
(basecoat + pearl midcoat +
clearcoat).

32. CLEAR COAT
Usually sprayed on top of a
coloured basecoat, clear coat is a
glossy and transparent coating
that forms the final interface
with the environment. For this
reason, clear coat must be
durable enough to resist abrasion
and chemically stable enough to
withstand UV light. Clear coat can
be either solvent or water-
borne. One part and two part
formulations are often referred
to as 1k and 2k respectively.

33. Table I: General Basecoat Formula
Petroleum –Based Solvents
Resins and Binders
Pigments & Colorants
Silicone Polymers & Other Additives
(Catalysts, etc.)
40-60%
30-50%
5-10%
1-2%
Table II: General Clear Coat Formula
Petroleum –Based Solvents
Resins and Binders
UV Absorbers
Silicone Polymers & Other Additives
(Catalysts, etc.)
20-40%
50-70%
1-2%
1-2%

34. Table III: General Wax Formula
Water
Petroleum –Based Solvents
Polishing Agents (Abrasives)
Natural and/or Synthetic Waxes
Silicone Polymers
Surfactants
Additives
(Fragrance, Thickeners, Preservatives, etc.)
30-60%
15-40%
10-30%
0-5%
0-5%
1-5%
0-3%

35. 1. Dry Terry Towel (8x)
2. Dry Micro Fibre Towel (8x)

36. 3. Leading brand per label
directions(8x)
4. Optimum Car Wax per label
directions (8x)