CHM 1020 Chapter 4

Which effect does a catalyst have on a chemical reaction?

A catalyst lowers the activation energy for a reaction

Which of these elements are common contaminants in coal?

Arsenic Sulfur Lead

Which of the following best describes the process of combustion?

Chemical combination with oxygen to release energy.

What is cellulosic ethanol?

Ethanol produced from inedible parts of plants

Which of the following are sources of renewable energy?

Hydropower Biofuels Wind

How do temperature and activation energy relate to affect a reaction?

Increasing temperature provides particles with more kinetic energy, so the activation energy is more easily overcome.

Which of the following options best describe isomers?

Isomers contain the same number and type of atoms, but they are connected in different ways.

During an energy conversion, what happens to the energy that is lost?

It becomes kinetic energy of random motion of the surrounding molecules.

Match the name of each alkane correctly to its chemical formula.

Methane - CH>4 Ethane - C>2H>6 n-pentane - C>5H>12 n-heptane - C>7H>16

Match each term to the correct definition

Temperature- Measure of the average kinetic energy of the atoms/ molecules in a substances Heat - Flow of energy between objects with different molecular kinetic energies

What is the biggest limitation in the production of petroleum products?

The amount of easily recoverable deposits

The bond energy of a C-H bond is ___.

The amount of energy consumed to break a C-H bond.

Activation energy is best described as ___.

The energy required to initiate a chemical reaction.

How is a calorie defined?

The energy to increase the temperature of 1 g of water by 1 degree Celsius

What is the most common effect of increasing temperature on a chemical reaction?

The reaction rate will increase

Glycerol is a by-product of biodiesel production.

True

Which of the following substances can be used to produce biodiesel?

Vegetable oil Animal fat

Biofuels are energy sources that are produced from ____ matter.

biological matter

The chemical definition of an alcohol is a molecule that ____.

contains a hydroxyl (OH) group

The measure of the amount of energy dispersed in a process is called ___.

entropy

A particular grouping of atoms that gives characteristic chemical and physical properties to a molecule that contains it is known as a ____ group.

functional group

A calorimeter is used to measure the ____ released or absorbed by a reaction.

heat

Which of these units are commonly used to express heats of combustion?

kcal/g kJ/mol

What compound makes up the majority of natural gas?

methane

When oil is burned in a power plant, the ___ energy of the oil is converted into heat, which increases the ___ energy of the water.

potential kinetic

Hydrocarbons with only ___ bonds between carbon atoms are called alkanes.

single

Energy conversion can never be 100% efficient because __

some amount of potential energy is always dissipated as heat

Equation that gives the net efficiency for an energy transformation in a power plant?

(electrical energy produced/heat from fuel) X100

Which of the following are true of biodiesel molecules?

--- Biodiesel molecules contain a "cap" from methanol or a similar alcohol. --- Biodiesel molecules contain a long hydrocarbon chain. --- Biodiesel molecules contain an ester functional group.

Which of the following statements describe cellulose?

--- Cellulose is a structural of plants. --- Cellulose is a polymer of glucose

Which of the following options correctly describe activation energy?

--- Increasing temperature allows more particles to have sufficient energy to overcome the activation energy barrier. --- Lower activation energy generally results in faster reactions.

Which of the following statements correctly describe petroleum?

--- It is made from partially decomposed organic matter. --- It is a mixture of many different compounds

Which of the following statements correctly describe the possible effects of different hydrocarbons on an internal combustion engine?

--- Knocking is a violent and uncontrolled reaction inside an engine cylinder --- Preignition occurs when cylinder compression alone can ignite a fuel.

Which of the properties make one grade of coal more desirable than another?

--- Lower oxygen content --- Lower sulfur content --- Higher C content

Which of the following products are separated from crude oil?

--- Starting materials for plastics and other carbon-based products --- Industrial oils and lubricants --- Jet fuel

Which of the following are issues raised by the 2011 Nuffeld Council report on biofuels ethics?

---Competition of biofuels with food crops. ---Loss of biodiversity to biofuels agriculture.

Which of these statements correctly describe coal mining?

---Mining debris can damage or bury nearby water systems. --- Near-surface coal can be mined more safely than other deposits.

Rank the grades of coal by their relative desirabilities, starting with the most desirable coal at the top of the list

1.) anthracite 2.) bituminous 3.) lignite

In the octane rating system, iso-octane is assigned a rating of ____, while n-heptane has an octane rating of ___.

100 0

Which of these statements correctly describe the Fischer-Tropsch process?

--- This is an example of a catalytic process. --- This process can be used to produce gasoline from coal.

Which of the following statements are true about triglycerides?

--- Trigycerides can be used to prepare biodiesel. --- A triglyceride molecule contains three hydrocarbon chains. --- Fats and oils consist of triglycerides.

Proposed "clean coal" technologies include which of the following techniques?

--- Washing to remove impurities before use --- Chemically removing SO>2 before releasing combustion products.

Which of the following options correctly explain why an energy change calculated using bond energies may not match experimental results

--- Bond energies are given for molecules in the gaseous state --- Bond energies vary between molecules, even for the same pair of elements.

Which of the following statements correctly describe bond energy?

--- Bond energy values are always positive. --- the total energy required to break bonds depends on the number of bonds.

Which of the following statements correctly describe photosynthesis?

--- It generates products with higher potential energy than its reactants --- It removes free CO>2 from the atmosphere --- It requires energy input to occur

Which of the following options correctly explain why petroleum has overtaken coal as the largest energy source in the United States?

--- It is easier to extract from underground. --- It produces more energy per gram than coal.

What are the biggest advantages of natural gas as a fuel source?

--- It leaves no ash residue --- It produces almost no sulfur oxides

Which statements describe steps in the production of fossil fuels?

--- Sunlight energy is captured by plants during photosynthesis. --- Plants partially decompose, releasing stored energy and producing H>2O and CO>2.

Which of the following statements correctly describe methods of improving the octane rating of gasoline?

--- Tetraethyl lead (now banned) served as an antiknock additive in gasoline --- Catalytic reforming can be used to create molecules with higher octane ratings

Which of the following are forms of potential energy?

--- The energy stored in the chemical bonds of a compound. --- The energy of an object suspended above the ground.

Which of the following options correctly describe fossil fuels?

--- They are not sustainable at the current rate of use. --- Their use raises atmospheric CO>2 levels.

What are the greatest advantages of biofuels?

--- They are renewable resources --- They can release less net CO>2 than fossil fuels.

Which of the following are advantages of oxygenated fuels?

--- They produce less CO than traditional gasoline. --- They enhance the octane rating of the gasoline

Which of the following options correctly describe internal combustion engines?

--- They use the gas products of combustion to drive mechanical pistons. --- They are less efficient than most power plants --- More than half the energy they produce is lost as heat

Which of the following reactions will release the most energy?

High-energy reactants form low-energy products.

Which of the following comprise the major component of petroleum?

Hydrocarbons

Which of the following comprise the largest component of gasoline?

Hydrocarbons with 5-12 carbon atoms

Place the following objects in order of increasing kinetic energy, with the least energy of the bottom.

1.) A semi-truck moving at 45 mph 2.) A car moving at 45 mph 3.) A car moving at 10 mph 4.) A bicycle moving at 10 mph

Place the steps for the production of ethanol from corn in order, with the first step at the top of the list.

1.) Corn kernels are mixed with water. 2.) Enzymes break down starches into glucose. 3.) Yeast fermentation converts sugars into ethanol. 4.) The mixture is distilled

The following are the steps seen when a Newton's cradle is used. Place them in the correct order, with the first step at the top.

1.) One ball is lifted by hand, giving it potential energy 2.) The ball is released, converting potential energy into kinetic energy as it falls. 3.) The falling ball strikes the unmoving balls, and kinetic energy is transferred through them to the ball on the opposite end. 4.) The opposite ball swings upward, converting its kinetic energy to potential energy.

Using the attached graph, rank the use of coal, petroleum, hydroelectric, and nuclear power as energy sources in the United States in the year 2000. Place the least used energy source at the bottom.

1.) Petroleum 2.) Coal 3.) Nuclear 4.) Hydroelectric

Place the steps for the distillation of crude oil in the proper order, beginning with the first step at the top of the list.

1.) The crude oil mixture is heated. 2.) Compounds with the lowest boiling points vaporize. 3.) High-boiling compounds vaporize. 4.) Vapors are separated in the fractionation tower. 5.) Products are condensed and collected.

Biodiesel is sold as a blend with petroleum-based diesel. Blends that contain up to _____% biodiesel are compatible with any diesel engine.

20%

If carbon (graphite) releases 394 kJ/mol when burned, how many kJ of energy are released for each g of carbon burned?

32.8 kJ

match each process correctly with the associated energy change

Bond breaking - absorbs energy Bond forming - releases energy

Match each reaction

Exothermic- A reaction that releases heat Endothermic - A reaction that absorbs heat

Why is biodiesel unique among transportation fuels?

It can be made readily in small batches by individuals

What is the modern metric unit of energy?

Joules (J)

What are reformulated gasolines?

Oxygenated gasolines with lower percentages of some volatile organic compounds

A sample of fuel is burned in oxygen, producing heat and light. Based on the first law of thermodynamics, which statement must be true?

the energy lost from the fuel and oxygen is equal to the energy of the heat and light.