Seminar:Test 2 Review

Freddie Arocho-PerezKaplan UniversitySC155: Introduction to Chemistry

General Information

Access Dates:Wednesday, Jan 13 – Sunday, Jan 24

During the time that the test is available, you may take it anytime you wish and as many times as you want. Only the last submission will be saved and graded.

I made it available for more time than I originally noted in the syllabus. The only reason I did this was because I assume most of you would like to work on this test on evenings and weekends.

General Information

Content: Units 5 – 9. The test is not cumulative; only units 5 – 9. The test consists of 24-multiple choice

questions. Each question is worth 5 points.

General Information

Study Guide will be sent by e-mail. The test questions will account for reading

comprehension, applications, and definitions. Useful Materials:

– Periodic Table (see DocSharing for a hand-out).– Seminar Presentations (see DocSharing for

copies).– Self-Assessments (see DocSharing for more

information).

Practice Question

What will happen to the volume of a gas if the pressure is decreased? Assume that the amount of gas and the temperature remain constant.

– The volume will decrease.– The volume and the temperature will remain the

same.– The volume will increase.– You need more information to answer this

question.

Practice Question

What will happen to the volume of a gas if the pressure is decreased? Assume that the amount of gas and the temperature remain constant.

– The volume will decrease.– The volume and the temperature will remain the

same.– The volume will increase.– You need more information to answer this

question.

Solution: Practice Question

Boyle’s Law:– P proportional to 1/V– “Bigger” the pressure means “smaller” the volume

Reducing the volume implies increasing the pressure at the same rate.

Reducing the pressure implies increasing the volume at the same rate.

The relation is “inversely” proportional.

Practice Question

In thermodynamics, what is the system?

– The part of the universe not being studied.– The surroundings.– The part of the universe being studied.– A state function.

Practice Question

In thermodynamics, what is the system?

– The part of the universe not being studied.– The surroundings.

– The part of the universe being studied.

– A state function.

Solution: Practice Question

System: part of the universe that is under consideration. A real or imaginary boundary separates the system from the rest of the universe, which is referred to as the environment or surroundings.

Surroundings: (or environment) are anything not part of the system. They are separated from the system by a real or imaginary boundary. Together with the system, they make up the universe. The surroundings do not contain any processes of interest. However, they can usually exchange energy and, sometimes, even matter with the system, influencing the processes that occur there.

Practice Question

Which of the following vitamins is classified as “water-soluble”?

– Vitamin A– Vitamin C– Vitamin D– Vitamin E

Practice Question

Which of the following vitamins is classified as “water-soluble”?

– Vitamin A

– Vitamin C– Vitamin D– Vitamin E

Solution: Practice Question

“Fat-Soluble” Vitamins:– A - D– E - K

“Water-Soluble” Vitamins:– C - B1– B2 - B3– B6 - B12– Folate - Biotin– Pantothenic Acid

Practice Question

A catalyst has which of the following properties?

– A catalyst decreases the enthalpy of a reaction.– A catalyst is completely consumed during a

reaction.– A catalyst increases the rate of a reaction.– A catalyst appears in the balanced reaction.

Practice Question

A catalyst has which of the following properties?

– A catalyst decreases the enthalpy of a reaction.– A catalyst is completely consumed during a

reaction.

– A catalyst increases the rate of a reaction.

– A catalyst appears in the balanced reaction.

Solution: Practice Question

Catalysts:– A catalyst is a compound that increases the rate of a

reaction by providing an alternative reaction mechanism, for a chemical process. This alternative mechanism has a lower activation energy.

– A catalyst is a substance that accelerates the rate of a chemical reaction but remains chemically unchanged afterwards.

– The catalyst increases rate reaction by providing a different reaction mechanism to occur with a lower enthalpy (energy).

Practice Question

CFC stands for __________.

– chlorinated freon compound.– chlorofluorocarbon.– carbonated fluorine compound.– caustic fluorine carbohydrate.

Practice Question

CFC stands for __________.

– chlorinated freon compound.

– chlorofluorocarbon.– carbonated fluorine compound.– caustic fluorine carbohydrate.

Solution: Practice Question

CFCs were used for years as aerosol propellants and refrigerants.

In 1974 Rowland and Molina discovered that chlorine from chlorofluorocarbons (CFCs) may be depleting the supply of ozone in the upper atmosphere by reacting with it.

They are not water soluble (so they do not get washed out of the atmosphere by rain) and are quite unreactive (so they are not degraded naturally).

Practice Question

Which of the following pH values indicates a acidic solution?

– 3– 7– 9– 12

Practice Question

Which of the following pH values indicates a acidic solution?

– 3– 7– 9– 12

Solution: Practice Question

The pH scale measures how acidic or basic a substance is.

The pH scale ranges from 0 to 14. A pH of 7 is neutral. A pH less than 7 is acidic. A pH greater than 7 is basic. Pure water is neutral. But when chemicals are mixed

with water, the mixture can become either acidic or basic. Examples of acidic substances are vinegar and lemon juice. Lye, milk of magnesia, and ammonia are examples of basic substances.

Practice Question

According to Charles's Law, what will happen to the temperature of a gas if the volume is decreased (while the gas remains at a constant pressure)?

– The temperature will remain the same.– The temperature will increase.– The temperature will decrease.– You cannot predict what will happen to the

temperature.

Practice Question

According to Charles's Law, what will happen to the temperature of a gas if the volume is decreased (while the gas remains at a constant pressure)?

– The temperature will remain the same.– The temperature will increase.– The temperature will decrease.– You cannot predict what will happen to the

temperature.

Solution: Practice Question

Charles’s Law– Charles’s Law states that under conditions of

constant pressure and quantity, there is a direct relationship between the volume and absolute temperature for an ideal gas.

Reducing the temperature implies reducing the volume at the same rate.

Increasing the volume implies increasing the temperature at the same rate.

The relation is “directly” proportional.

Practice Question

What is the First Law of Thermodynamics?

– Matter is neither created nor destroyed.– The total energy in the universe is constant.– All systems receive work from their surroundings.– Matter can be converted to energy and vice versa.

Practice Question

What is the First Law of Thermodynamics?

– Matter is neither created nor destroyed.

– The total energy in the universe is constant.

– All systems receive work from their surroundings.– Matter can be converted to energy and vice versa.

Solution: Practice Question

The First Law of Thermodynamics:– Conservation of Energy: states that energy is always

conserved, it cannot be created or destroyed.– The total energy in the universe is constant.

The Law of Conservation of Mass:– This law indicates that mass cannot be created or destroyed.

The Second Law of Thermodynamics:– States that the entropy of the universe always increases, or

(equivalently) that perpetual motion machines are impossible. The Third Law of Thermodynamics:

– Concerns the entropy of an object at absolute zero temperature, and implies that it is impossible to cool a system all the way to exactly absolute zero.

Practice Question

What does the term “forensic” mean? - pertaining to medicine- pertaining to the law- pertaining to death- pertaining to crime

Practice Question

What does the term “forensic” mean? - pertaining to medicine

- pertaining to the law- pertaining to death- pertaining to crime

Solution: Practice Question

The application of science to those criminal and civil laws that are enforced in the justice system.

Any application of science to law enforcement.

Practice Question

Which of the following describes an endothermic reaction?

– A reaction that moves heat from the surroundings into the system.

– A reaction that moves heat from the system into the surroundings.

– A reaction that causes the temperature of the surroundings to rise.

– A reaction in which the change in enthalpy is less than zero.

Practice Question

Which of the following describes an endothermic reaction?

– A reaction that moves heat from the surroundings into the system.

– A reaction that moves heat from the system into the surroundings.

– A reaction that causes the temperature of the surroundings to rise.

– A reaction in which the change in enthalpy is less than zero.

Solution: Practice Question

An endothermic reaction soaks up heat.– System receives the energy (heat) from the

surroundings. An exothermic reaction releases heat.

– System releases the energy (heat) to the surroundings.

“Endothermic”: Absorbs “Exothermic”: Releases

Practice Question

Which statement about organic chemistry is not correct?

– Organic chemistry involves the study of carbon-containing compounds.

– Organic compounds, which contain carbon and hydrogen, are vital to all living systems.

– Only a few molecules have carbon as their central, core atom(s).

– Organic chemistry is an entire branch of chemistry dedicated to carbon.

Practice Question

Which statement about organic chemistry is not correct?

– Organic chemistry involves the study of carbon-containing compounds.

– Organic compounds, which contain carbon and hydrogen, are vital to all living systems.

– Only a few molecules have carbon as their central, core atom(s).

– Organic chemistry is an entire branch of chemistry dedicated to carbon.

Solution: Practice Question

Organic Chemistry:– Discipline within Chemistry that involves the scientific

study of the structure, properties, composition, reactions, and preparation of compounds that contain carbon.

– These compounds may contain any number of other elements, including hydrogen, oxygen, nitrogen, chlorine, silicon, and bromine.

– Carbon is the central atom in all of these compounds.

Practice Question

Hydrocarbons contain only hydrogen and carbon. Which of the following is not a class of pure hydrocarbons?

– Alkynes– Alcohols– Alkenes– Alkanes

Practice Question

Hydrocarbons contain only hydrogen and carbon. Which of the following is not a class of pure hydrocarbons?

– Alkynes

– Alcohols– Alkenes– Alkanes

Solution: Practice Question

Alkanes, Alkenes, Alkynes: Compounds composed of only carbon and hydrogen.

Alcohol: Compounds composed of carbon, hydrogen, and oxygen.

Reflecting on the Course…

Exploring the fundamental theories of chemistry. Emphasis on the chemical processes that affect

our lives. Learning how to apply new knowledge about a

variety of topics to better understand the natural and human-made world.

Discussion Topics: Applications, Real-Life Seminar Topics: Theory, Applications, Real-Life

Reflecting on the Course…

Applications:– Environment:

Ozone Global Warming

– “Green Chemistry”– Energy/Alternative Resources– Health/Nutrition– Forensics– Nanotechnology– Drugs/Pharmaceuticals

Reflecting on the Course…

Project Topics: Theory, Applications– First Project: Atomic Model/Periodic Table– Second Project: Environment/Energy– Third Project: Health/Nutrition

Adventure of self-exploration, as well as establishing a firm science base for other courses you will take in the future.

Professional Preparation.

A Message for You…

“Life is too short to wake up with regrets. So love the people who treat you right. Forget about the one's who don’t. Believe everything happens for a reason. If you get a second chance, grab it with both hands. If it changes your life, let it. Nobody said life would be easy, they just promised it would be worth it.”

Thank you for letting me to help you to learn some important aspects of Chemistry!!!

God bless you.- Freddie

Reach your Goals!!!