1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
valkas [14]
3 years ago
12

PLS HELP,WILL GIVE BRAINLIEST + 30 POINTS

Physics
1 answer:
mixer [17]3 years ago
3 0

Answer:

☟

Explanation:

Fuels made from oil mixtures containing large hydrocarbon molecules are not efficient as they do not flow easily and are difficult to ignite. Crude oil often contains too many large hydrocarbon molecules and not enough small hydrocarbon molecules to meet demand. This is where cracking comes in.

Cracking allows large hydrocarbon molecules to be broken down into smaller, more useful hydrocarbon molecules. Fractions containing large hydrocarbon molecules are heated to vaporise them. They are then either:

heated to 600-700°C

passed over a catalyst of silica or alumina

These processes break covalent bonds in the molecules, causing thermal decompositionreactions. Cracking produces smaller alkanesand alkenes (hydrocarbons that contain carbon-carbon double bonds). For example:

hexane → butane + ethene

C6H14 → C4H10 + C2H4

Some of the smaller hydrocarbons formed by cracking are used as fuels, and the alkenes are used to make polymers in plastics manufacture. Sometimes, hydrogen is also produced during cracking.

Fractional distillation of crude oil

Fractional distillation separates a mixture into a number of different parts, called fractions.

A tall fractionating column is fitted above the mixture, with several condensers coming off at different heights. The column is hot at the bottom and cool at the top. Substances with high boiling points condense at the bottom and substances with lower boiling points condense on the way to the top.

Crude oil is a mixture of hydrocarbons. The crude oil is evaporated and its vapours condense at different temperatures in the fractionating column. Each fraction contains hydrocarbon molecules with a similar number of carbon atoms and a similar range of boiling points.

Oil fractions

The diagram below summarises the main fractions from crude oil and their uses, and the trends in properties. Note that the gases leave at the top of the column, the liquids condense in the middle and the solids stay at the bottom.

As you go up the fractionating column, the hydrocarbons have:

lower boiling points

lower viscosity (they flow more easily)

higher flammability (they ignite more easily).

Other fossil fuels

Crude oil is not the only fossil fuel.

Natural gas mainly consists of methane. It is used in domestic boilers, cookers and Bunsen burners, as well as in some power stations.

Coal was formed from the remains of ancient forests. It can be burned in power stations. Coal is mainly carbon but it may also contain sulfur compounds, which produce sulfur dioxide when the coal is burned. This gas is a cause of acid rain. Also, as all fossil fuels contain carbon, the burning of any fossil fuel will contribute to global warming due to the production of carbon dioxide.

You might be interested in
List some things in your house that has the same density....
natali 33 [55]
Same Density as what??
4 0
3 years ago
Explain how high-pressure and low pressure systems are different
Studentka2010 [4]
Low pressure has a bit less of a function than high pressure, high pressure is more useful in certain terms
5 0
3 years ago
A trough is 10 feet long and its ends have the shape of isosceles triangles that are 3 feet across at the top and 1 foot high. I
tensa zangetsu [6.8K]

Answer:

1.6 ft/min

Explanation:

Since trough is 10 ft long and water is filled at the rate of 12ft3/min. We can calculate the rate of water filled with respect to area:

= 12 / 10 = 1.2ft2/min

As the water level rises, so does the water surface, or the bottom side of the isosceles triangles. In fact we can calculate the bottom side when the trough is half foot deep:

= 3 / 2 = 1.5 ft

The rate of change in water level would be the same as calculating the height of the isosceles triangles knowing its base

= 1.2 * 2 / 1.5 = 1.6 ft/min

6 0
3 years ago
A race car makes three and half laps around a circular track in 4.5 min. What is the car’s angular speed?
slavikrds [6]

Answer:

the angular speed is around 45

Explanation:

7 0
3 years ago
Which of the following is not a synthesis reaction?
Nastasia [14]
C is the awnser because c is single replacement
6 0
3 years ago
Other questions:
  • Displacement vectors of 3 m and 5 m in the same direction combine to ma
    6·1 answer
  • Our Sun will eventually:
    6·2 answers
  • In an overhead camshaft engine, the lobes make direct contact with the 
    15·2 answers
  • A slinky is stretched across a classroom and moved up and down at a frequency of 2 hz. if the corresponding wave velocity is 4.2
    10·1 answer
  • According to the kinetic theory, all matter is composed of _______.
    11·2 answers
  • According to Faraday's law, voltage cannot be changed by changing the magnetic field strength.
    9·1 answer
  • Un auto recorre una carretera en línea recta de 10km y tarda 8 minutos ¿Cual es su velocidad en km/h?
    14·1 answer
  • On a hot summer day, you need to leave your house for 30 minutes. To use the least amount of energy, should you turn off your ai
    8·1 answer
  • A uniformly charged rod of length L = 1.3 m lies along the x-axis with its right end at the origin. The rod has a total charge o
    11·1 answer
  • You normally drive on the freeway between San Diego and Los Angeles at an average speed of 105 km/h (65 mi/h), and the trip take
    12·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!