Mrs. Garth's Chemistry Chapter 2

Physical Properties

A characteristic of a pure substance that can be observed without changing it into another substance.

What must occur in a substance in order to determine a chemical property?

A chemical property can be determined only when a change in the substance occurs in the presence of another substance or when sufficient energy of some form is added to it.

Heterogeneous Mixtures

A mixture in which different materials can be distinguished easily

What is a physical change? Give three examples of physical changes.

A physical change results only in a rearrangement of the particles of matter, not in their composition. Examples include crushing, dissolving, hammering into a thin sheet, or changing state.

Differentiate between physical and chemical properties of matter. Give two examples of each property.

A physical property of matter can be determined or observed without altering the chemical composition of the matter. Examples include color, hardness, electrical conductivity and malleability. A chemical property can be determined only through a change to the material that permanently alters its composition. Examples include combustion in the presence of oxygen and decomposition in the presence of an electrical current.

Endothermic Reaction

A reaction that ABSORBS energy in the form of heat

Exothermic Reaction

A reaction that releases energy in the form of heat

Liquid

A state of matter that has no definite shape but has a definite volume., assumes shape of container, packed close together, difficult to compress

Gas

A state of matter with no definite shape or volume, restricted only by its container as far as shape and volume; particles are easy to compress

_____________cannot be reached at a given location because there cannot be a colder place where thermal energy can flow to in order to cool the location.

Absolute Zero

Where did Matter come from?

All matter was created during the events of Creation Week when it was spoken into existence by God.

Compare and contrast gases and plasma.

Both gases and plasmas consist of energetic particles that are so far apart that attractive forces between particles are inconsequential. They are both highly compressible, have no definite volume, and can diffuse to occupy a volume of space. In contrast, gases consist of intact atoms or molecules, while the particle in plasmas are mostly ions and free electrons. The temperature of plasmas are usually several orders of magnitude higher than that of gases.

A Kelvin degree is the same size unit as a _____________ degree

Celsius

Chemical Properties

Characteristic that cannot be observed without altering the substance

A ___________ property of a substance cannot be determined without causing a or attempting to cause a chemical change to occur in the substance.

Chemical

Name the change of state that are described by the following process: Water mist collects on the bathroom mirror after a shower.

Condensation

Explain the difference between heterogeneous and homogeneous mixtures.

Heterogeneous mixtures consist of two or more materials segregated into distinct pieces, regions, or phases (e.g. granite). A homogeneous mixture is a physical combination of two or more pure substances where the individual particles of the substances are uniformly distributed throughout the mixture (e.g. salt water).

Thermal energy always flows from a ______ temperature to a _________ one

Higher.........Lower

A solution, such as filtered air, is a _________ mixture.

Homogeneous

Who was the modern system of chemical symbols developed by?

Hons Berzelius.

What is matter?

Matter is anything that occupies space and has mass.

Name the change of state that are described by the following process:As a candle burns, wax drips down the sides of the candle.

Melting

The _______ is identical to the ___________of a substance.

Melting point...........Freezing piont

Homogeneous Mixtures

Mixtures with the same appearance and properties throughout it

Energy

Operationally defined as the ability to do work

Name the change of state that are described by the following process: You smell the odor of moth balls when you open a clothes box.

Sublimation

How do Pure Substances differ from mixtures?

The particles in pure substances consist of all one kind of atom (a single element) or those that make up only one compound. Pure substances differ from mixtures in that mixtures are combinations of two or more substances that are not chemically combined.

Why are solids and liquids relatively incompressible?

The particles in solids and liquids are so close together that they cannot be squeezed any closer. The structure of atoms prevents two atoms from occupying the same space at the same time.

Joule

The scientific unit for energy and work

Why is Creation ex nihilo religious belief and not a scientific fact?

The special creation of the universe and everything in it was not and is not observable by humans, and is therefore outside the realm of observational science. To accept the declarations of Scripture must be done in faith, which is one of the foundations of Christianity.

Explain the difference between temperature and thermal energy.

The thermal energy contained in a system is the total kinetic energy of the particles in the system. Temperature is a property that is proportional to the average kinetic energy of the system's particles. Thermal energy is related to the quantity of matter present; temperature is not.

When you grasp a hot cup of cocoa with cold hands, which way does the heat transfer occur? Explain

The thermal energy flows from the hot cup into the cold hands until they are the same temperature. Heat transfers always occur from higher temperature to lower temperatures according to the second law of thermodynamics.

What are the two main classes of matter and what characteristics differentiate them?

The two main classes of matter are pure substances and mixtures. A pure substance consists of only one kid of matter that is chemically combined (an element or a compound). A mixture is a physical combination of two or more substances.

Molecules consisting of __________ elements are the smallest identifiable particles of noncrystalline compounds

Two or more

Name the change of state that are described by the following process: The fragrance of an open perfume bottle is smelled from across the room.

Vaporization

Name the change of state that are described by the following process: Water leaves a teakettle that is sitting on a hot stove.

Vaporization

Element

a pure substance that cannot be broken down into a simpler substance by ordinary chemical means

Third law of thermodynamics.

absolute zero cannot be reached

Thermal energy, does not _______ for the potential energies of the particles in a system.

account

Internal energy

accounts for the potential energies of the particles in a system.

What is the principal type of energy involved in vibrations from a loudspeaker

acoustic or sound energy

Ion

an atom that is charged

Temperature measures the _______kinetic energy in a sample

average

First law of thermodynamics.

energy is neither created nor destroyed, but may be converted from one form to another

Plasma

gas-like state at very high temperatures; particles are ions, electrons, and neutral atoms traveling at extremely high speeds, no definite shape or volume, can be affected by a magnetic field

Mixture

material that can be separated into two or more pure substances

Malleability

materials that can be hammered easily into thin sheets or shapes

What is the principal type of energy involved in a rolling ball

mechanical (kinetic) energy

Kelvin temperatures can never have __________ values

negative

What is the principal type of energy involved in changes occurring at the center of a star

nuclear energy

ex nihilo

out of nothing This phrase describes the manner in which God created all things

List the known states of matter in order form the most energetic to the least.

plasma, gas, liquid, solid

System

portion of the universe under study in thermodynamics, and it has distinct boundaries

Atoms

the basic particles that makes up elements

Entropy

the measure of randomness or disorder in a system

Absolute Zero (0 degrees Kelvin)

the theoretical temperature at which all molecular and atomic movement ceases.

What is the principal type of energy involved in a pot of near-boiling water

thermal energy

Thermal energy measures the _______kinetic energy in a sample

total

Ductility

Materials that can be drawn into long thin wires

What property of metal does shot peening use?

Shot peening uses the malleability of metal to increase its strength.

How does an ion differ from an atom?

An ion is a charged atom in which there is a mismatch of electrons and protons. An atom is assumed to be uncharged.

Matter

Anything that has mass and takes up space

Matter can neither be ________________ or ______________________

Created........Destroyed

Solid

Definite shape and volume, difficult to compress, packed close together, rigidly held

Name the change of state that are described by the following process: Frost patterns appear on a cold window pane in winter.

Deposition

During what meteorological (weather) changes does deposition occur on earth?

Deposition occurs whenever frost or snowflakes form. These are very common processes over much of the earth's surface.

State three evidences that the particles of substance are in continuous motion.

Diffusion of perfume odors in air, evaporation of steam droplets in air, and Brownian motion in microscopic objects.

A toaster converts ___________ energy to ____________ energy

Electromagnetic to Thermal

In order to be useful, _______ must often be converted from one form to another.

Energy

Is energy something a system does or something it has?

Energy is something a system has. The energy of a system consists of the motion of a system's particles as well as the motion of the system as a whole. If the system transfers its energy to something else, it does work.

Burning a candle is an _____________ reaction

Exothermic

Liquids flow only when a _________ acts on them.

Force

Name the change of state that are described by the following process: pond water solidifies on a cold winter day.

Freezing

Since heat transfers only take place between systems with different temperatures, explain why the third law of thermodynamics is support by our current understanding of matter.

In order to cool a point to absolute zero, the thermal energy in the particles at that point would have to flow to a colder spot, which is impossible, since there is no point colder than absolute zero by definition.

What does the first law of Thermodynamics imply for the origins of matter and energy?

It implies that, barring miracles, there must have been a beginning of creation to account for both the energy and matter in the universe.

Scientific unit for energy

Joule

What is the scientific unit for energy and work?

Joule

scientific unit for work

Joule

Mechanical Energy can be divided into two different types of Energy.....

Kinetic and Potential

How is shot peening an example of using technology to exercise dominion and to love your neighbor as yourself?

Loss of life and expense as well as exploitation of the natural resource God has given us can all be avoided with a process like shot or laser peening.

What condition distinguishes plasmas from more "normal" states of matter?

Plasmas occur only at extremely high temperatures (defined by the energy of the individual particles).

Second law of thermodynamics.

Says that the entropy (disorder) of the universe is increasing. Every energy transfer or transformation increases the entropy of the universe.

One of the difficulties with the big bang origin of the universe is that many evidence predicted by the theory are not ________ in the universe today or are contradict by other evidence.

Seen

Conductivity

The ability of a material to transfer heat or electricity between its particles

Density

The amount of matter packed into a given volume. Mass / Volume

What invention spurred the development of thermodynamics?

The area developed as a result of the invention of the steam engine.

Compare the entropy of a firecracker before it is lighted to its entropy after it explodes. Explain the difference.

The firecracker's entropy after it has burst is greater than before it is lighted. The firecracker has less usable energy and its parts are more disorganized (less ordered) after it explodes.

Why is the joule the preferred unit of energy in scientific studies? What part of the definition of the calorie could make it more convenient for use in non-scientific studies?

The joule is the SI unit for any form of energy, which is derived from fundamental SI units. The joule is not restricted to a particular kind of energy. The calorie is defined as the heat transfer required to change the temperature of 1 g of water 1 ° C. These are easily measured units for many kinds of work.

Why do some chemical symbols for elements consist of two letters and other of only one?

There are more elements than letters of the alphabet, so some symbols must use two letters to prevent confusion between elements. Because some elements begin with the same letter, a second letter is added to discriminate between them.

When an object cools, it losses _________________energy

Thermal

What specifically does thermodynamics investigate?

Thermodynamics is the study of the movement and conversion of energy. (especially thermal energy)

E = mc2

This famous equation from Einstein's special theory of relativity quantifies how much energy could be obtained if a certain amount of mater were converted to pure energy. It shows the equivalence of energy and matter.

What kind of change does shot peening cause in a sheet of metal? Why is it that type of change?

This is an example of a physical change because the substance is not changed.

Pure Substance

can be separated into other kinds of matter, but only by a chemical change

What is the principal type of energy involved in the source of an explosion of dynamite

chemical energy

Visible light is a form of ____________________ energy

electromagnetic energy

What is the principal type of energy involved in a camera flash

electromagnetic energy