3.2 and 3.3 - I can recall the general formula and displayed formulae of alkanes

What is the general formula for the alkanes?

C_nH_2n+2

Describe and explain the trend in boiling points.
_{As the number of atoms increases, from methane to pentane, the boiling point increases as well because the number of atoms and bonds in the molecules increaes. This means that more energy, heat, is required to turn the hydrocarbon into a gas. This is beuse there are more intermolecular forces which exists between the molecules. ay}          

3.4 I can recall the products of complete and incomplete combustion of alkenes

1.       Saturated hydrocarbons are called Alkanes

2.       Small chain Alkanes are used as fuels

3.       The reaction is called combustion.

4.       The word equation for  this chemical reaction is :

fuel (Alkane) + oxygen → carbon dioxide + water + ENERGY (heat, light, sound)

5.       If there is insufficient oxygen then the word equation is:

fuel (Alkane) + oxygen → carbon monoxide +  water  + ENERGY (heat, light, sound)

6.       The problem with this reaction is that carbon monoxide produced this gas is a toxic gas to the human body (see objective 5.11)

7.       Where can you find incomplete combustion?

            In car engines

8.       What is used to reduce the harmful products from incomplete combustion?

            A catalytic converter

9.       During incomplete combustion a smoky flame is often seen, explain this observation

            The smoky flame is produced by unburnt, solid, carbon molecules floating in the air - soot.

Extn: write a balanced equation (with state symbols) for the combustion of propane gas

     

C₃H_{8 (g)} + 5O_{2 (g)}  →  3CO_{2 (g)} + 4H₂O _(L)

3.1 - I can explain the terms homologous series, hydrocarbon, saturated, unsaturated, general formula and isomerism

Term	Definition	Example
Homologous series	A family of hydrocarbons with the same general formula.
Hydrocarbon	A molecule consisting only of hydrogen and carbon atoms.	Methane
Saturated hydrocarbon	A hydrocarbon with only single covalent bonds which can not hold any more atoms with out additional bonds being formed.	Pentane
Unsaturated hydrocarbon	A hydrocarbon containing double or triple covalent bonds that can hold additional atoms without creating any more bonds, but only by moving bonds.	Butene
General formula	A mathmatical formula that applies to an entire homologous series and will allow one to find the number of hydrogen atoms in a certain hydrocarbon based on the number of carbon atoms in the molecule.
Isomerism	The trait of molecules to become isomers. An isomer is a hydrocarbon with the same molecular formula as it's corresponding hydrocarbon, but with a different atomic arrangement.	2,2 dimethylpropane

5.13 - I describe the catalytic cracking of long-chain hydrocarbons.

1. A Catalyst is a substance that changes the rate of a reaction without being used up itself.

2. A Catalyst (silica or alumina in this case) is used in the process of catalytic cracking to increase the rate of reaction. This increases the amount of short- chain molecules that one can produce in a shorter amount of time. In turn, this increases the profits of the oil company and produces more useful hydrocarbons more quickly.

3. A high temperature (600 - 700 degrees Celsius) is used during the process of catalytic cracking. This high temperature is necessary because it increases the rate of reaction further and provides additional energy that is used to break the bonds of the long-chain hydrocarbons more effectively. This increases the output of short-chain hydrocarbons and increases the profits of the oil company.

5.12 - I recall that fractional distillation of crude oil produces more long-chain hydrocarbons than can be used directly and fewer short-chain hydrocarbons than required

a.       When crude oil undergoes Fractional Distillation there are too many large chain hydrocarbons (eg Fuel oil and Bitumen) produced and not enough small chain hydrocarbons (eg Gasoline and Refinery Gases).

b.      To solve these problems the large chain hydrocarbons undergo a chemical reaction called Cracking.

5.11 - I can recall how nitrogen oxides are formed in car engines

a.       Write the general equation for the combustion of a fuel	Fuel + Oxygen  Carbon Dioxide + Water + Energy
b.      During combustion the nitrogen in air can react to form what gases?	During combustion nitrogen may react with oxygen to form Nitrogen Oxides or NOx gases.
c.       What condition is necessary for the formation of these gases?	In order for the Nitrogen and Oxygen in the air to react during combustion, an extremely high temperature is necessary.
d.      In what common object is this condition found?	The high temperature necessary to form NOx gases can be found in the combustion engine of an automobile or car.
e.      Why is this condition needed for nitrogen to react?	A high temperature is necessary because it provides the energy needed to break to strong, triple covalent bond between the Nitrogen atoms. Ultimately, the high temperature allows the reaction to take place by causing the Nitrogen to become reactive instead of inert.
f.        What are the dangers of the products from this reaction?	The NOx gases have several dangerous properties. When dissociated in water, they form Nitric acid, which contributes to acid rain. In addition, the NOx gases can cause Asthma, nausea, may agitate tissues, and overall can remove up to nine years from one’s lifespan.

5.7 - describe how the industrial process of fractional distillation separates crude oil into fractions

5.10 recall that incomplete combustion of fuels may produce carbon monoxide and explain that carbon monoxide is poisonous because it reduces the capacity of the blood to carry oxygen

       

What are the properties of carbon monoxide?    Carbon Monoxide is a colourless, odourless, tasteless gas that is roughly the same density as air. Carbon Monoxide has a higher affinity for haemoglobin than Oxygen and bonds more quickly with red blood cells. This results in rapid and intense Oxygen deprivation and can be fatal.

Explain how carbon monoxide is formed.    Carbon Monoxide is formed through incomplete combustion. When a flame is burning in oxygen, the oxygen is normally used in the combustion to make Carbon Dioxide (One Carbon and two Oxygen molecules). However, when there is not enough oxygen in the air around the flame to complete the combustion reaction, Carbon Monoxide (One Carbon and one Oxygen molecule) is formed instead of the Carbon Dioxide.

Explain why carbon monoxide is poisonous.    Carbon Monoxide has a higher affinity for haemoglobin than Oxygen and bonds more quickly with red blood cells. This results in rapid and intense Oxygen deprivation because the Oxygen is unable to bond with the red blood cells and cannot reach one’s vital organs. Carbon Monoxide poisoning is basically a form of suffocation.

5.9 - I can describe the trend in boiling point and viscosity of the main fractions

a.       What is the trend in boiling point of the fractions?	In the image the boiling point increases from right to left. The fraction with the lowest boiling point is the refinery gases, then gasoline, kerosene, diesel oil, fuel oil, and the fraction with the highest boiling point is bitumen.
b.      Define viscosity (source your definition)	The resistance of a fluid to shear or tensile force. Source: Wikipedia.
c.       What is the trend in viscosity of the fractions?	The fraction with the lowest viscosity is the refinery gases, then gasoline, kerosene, diesel oil, fuel oil, and bitumen is the most viscous fraction. In the image the viscosity increases from right to left.
d.      What is the trend in colour of the fractions?	The refinery gases are the lightest color (clear) and the fractions get progressively darker as one goes from right to left in the image. Gasoline is darker than the refinery gases; kerosene is darker than gasoline, and so on so forth. Bitumen is the darkest fraction as it is a dark brown or black color.
e.      Why is crude oil separated into fractions?	Crude oil is useless on its own, but when the crude oil mixture is separated into its many different substances, each fraction is very useful. So, in order to allow humans to take full advantage of crude oil, we must separate it into fractions.
f.        What process is used to separate crude oil into fractions?	The process used to separate crude oil into fractions is call Fractional Distillation.
g.       What physical property allows this process to work?	Each different hydrocarbon in crude oil has a different boiling point. Because of the differences in their boiling points, the crude oil can be separated into different fractions via Fractional Distillation.

5.8 - Recall the names and uses of the main fractions obtained from crude oil: refinery gases, gasoline, kerosene, diesel, fuel oil, and bitumen.

Mnemonic for the Fractional Distillation of Crude Oil

 

Refinery Gases Gasoline Kerosine Diesel Oil Fuel Oil Bitumen

Real Guns Kill Deer by Firing Bullets

5.6 I can recall what crude oil is made from

3.       Complete the following in a table with white text as the answer or as a rollover (no need for a table) and upload to your blog

a. Define the word hydrocarbon….	A hydrocarbon is a compound containing only hydrogen and carbon.
b. What is crude oil made from?	Crude Oil is a mixture of several hydrocarbons. It could also be described as the remains of prehistoric sea creatures.
c. Define the word compound….	A compound is two or more elements chemically bonded together to form a single molecule.
d. Define the word mixture…..	A mixture is made up of several compounds or elements mixed together without any chemical bonds.

4.       Read pgs 140 & 141 Chem 4 You and add these to the table above

d. How long does crude oil take to make?	Crude Oil takes millions of years to make, approximately 150 million years.
e. Where does the energy in crude oil originally come from?	All the energy in Crude Oil originally came from the sun. The animals and plants that make up Crude Oil produced energy using the sun and this same energy was trapped in the Crude Oil alongside the animals.
f. How is crude oil different from coal?	Crude Oil is a hydrocarbon while Coal is not. Coal is not a hydrocarbon because it contains other elements, like oxygen, as well as hydrogen and carbon. Moreover, coal is a solid and oil is a liquid.
g. Crude oil, coal and natural gas are collectively known as _________ fuels	Fossil. Crude oil, Coal ,and natural gas are known as fossil fuels because the animals and plants which beccame these fuels were prehistoric and were fossilized befor becoming oil.
h. How is crude oil transported when it is extracted from the ground?	There are two methods that are used to transport oil. One is via the sea, on massive oil tankers. The ships are able to bring the oil all around the world. The other method is via a pipeline. THe oil is pumped through a pipe in order to reach its destination.

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