Physical Science

Question 1

Chemistry

Answer 1

the study of elements and the compounds
they form. Matter can take the form of an element, a
compound, or a mixture.

Question 2

Element

Answer 2

the basic form of matter, incapable
of being decomposed by chemical means into simpler
substances. Each element has distinct chemical and
physical characteristics. Hydrogen (H), oxygen (O),
and carbon (C) are elements.

Question 3

Compound

Answer 3

a combination of two or more
elements chemically combined in a specific proportion.
Compounds can be separated by chemical means,
and are represented by chemical formulas that include
the symbols of all the elements present. Examples of
familiar compounds are water (H2O) and table salt
(NaCl). In order to be considered organic, a compound
must contain carbon.

Question 4

Mixture

Answer 4

a combination of two or more substances
that are not chemically combined. Dissolving
salt in water results in a mixture. The two compounds
don’t react with each other and can be separated by
physical means—in this case, heating the water so it
evaporates, leaving the salt behind.

Question 5

Atom

Answer 5

the smallest unit of an element that retains
all of the element’s chemical properties. An atom
is composed of three primary particles: electrons,
protons, and neutrons.

Question 6

Electron

Answer 6

found outside the nucleus (the center of
an atom), it has a negligible mass and a charge
of –1.

Question 7

Proton

Answer 7

found in the nucleus, it has a mass of 1

amu (atomic mass unit) and a charge of +1.

Question 8

Neutron

Answer 8

found in the nucleus, it has a mass of 1

amu and no charge.

Question 9

Atomic number

Answer 9

the number of protons in the atom. The atomic number determines the element.

Question 10

Mass number

Answer 10

the total number of protons and
neutrons in one atom of an element. Mass number
can vary because the number of neutrons in an atom
can change.

Question 11

Solid

Answer 11

Retains a fixed volume and shape

• Not easily compressible
• Does not flow easily

Question 12

Liquid

Answer 12

Assumes the shape of the part of the container which it occupies

• Not easily compressible
• Flows easily

Question 13

Gas

Answer 13

• Assumes the shape and volume of its container
• Compressible
• Flows easily

Question 14

Combined Gas Law

Answer 14

According to the law, if volume remains constant,

pressure will change in proportion to temperature.

Question 15

Dalton Model

Answer 15

1803 John Dalton proposed an “atomic theory” with spherical solid atoms based upon measurable properties of mass. “Solid Sphere Model”

Question 16

Thomson Model

Answer 16

1898 JJ Thomson used a CRT to experimentally determine the charge to mass ratio of an electron. “Plum Pudding Model” / Electrons

Question 17

Rutherford Model

Answer 17

•1911 Rutherford Nucleus is dense, small, and positively charged. Electrons are located outside the nucleus. “Planetary Model” / Nucleus

Question 18

Bohr Model

Answer 18

•1922 Niels Bohr Developed an explanation of atomic structure that underlies regularities of the periodic table of elements. “Electron Shells”

Question 19

Alloy

Answer 19

A homogeneous mixture or solid solution of two or
more metals, the atoms of one replacing or occupying
interstitial positions between the atoms of the other.

Question 20

Combination (synthesis) reaction

Answer 20

where two or more substances are bonded together to produce a single product.
A reaction of the type: A + B –> AB

Question 21

Decomposition

Answer 21

the fragmentation of a chemical compound into elements or smaller compounds.
A reaction of the type: AB –> A + B

Question 22

Double-displacement reaction

Answer 22

where parts of two reacting structures swap places. A reaction of the type: AB + CD –> AD + CB

Question 23

Single-displacement reaction

Answer 23

where one element appears to move out of one compound and into another. A reaction of the type: A + BX –> AX + B

Question 24

Hooke’s Law

Answer 24

Hooke’s Law of elasticity is an approximation that states that the amount by which a material body is deformed (the strain) is related to the force causing the deformation (the stress).

Question 25

Newton's First Law

Answer 25

An object will stay at rest or move at a constant velocity (constant speed in a straight line) unless acted upon by an unbalanced force.

Question 26

Newton's Second Law

Answer 26

The rate of change of the momentum of a body is directly proportional to the net force acting on it, and the direction of the change in momentum takes place in the direction of the net force

Question 27

Newton's Third Law

Answer 27

For every action (force applied) there is an equal but opposite reaction (equal force applied in the opposite direction).

Question 28

Frequency

Answer 28

the measurement of the number of times a repeated event occurs per unit of time.

Question 29

Doppler Effect

Answer 29

the apparent change in frequency and wavelength of a wave that is perceived by an observer moving relative to the source of the waves.

Question 30

Diffraction

Answer 30

the bending of waves around obstacles and the spreading out of waves beyond openings.

Question 31

Series Circuits

Answer 31

Current remains constant but voltage drops differently across components of the circuit that have resistance.

Question 32

Parallel Circuits

Answer 32

Voltages across components are the same, but each component drops different amounts of current.

Question 33

Conservation of energy

Answer 33

The total amount of energy (including potential energy) in a closed system remains constant. In other words, energy can be converted from one form to another, but it cannot be created or destroyed.

Question 34

Energy input / output

Answer 34

the kind of energy that goes into a system and the resultant energy that comes out of a system; excess energy input deals with how much energy remains in a system that is not output; (ex. incoming solar radiation minus the infrared radiation back into space)

Question 35

Entropy

Answer 35

the measure of unavailable energy in a closed system / most common reference to entropy is found in thermodynamic systems

Question 36

Energy loss

Answer 36

energy that is not used to complete the intended processes of a system (ex. waste heat from an incandescent bulb or motor)

Question 37

Alpha decay

Answer 37

A form of radioactive decay in which an atomic nucleus ejects an alpha particle through the electromagnetic force And transforms into a nucleus with mass number 4 less and atomic number 2 less.

Question 38

Beta decay

Answer 38

A form of radioactive decay in which a beta particle (an electron or a positron) is emitted.

Question 39

Fission

Answer 39

A process in nuclear physics in which the nucleus of an atom splits into two or more smaller nuclei as fission products, and usually some by-product particles.

Question 40

Fusion

Answer 40

A nuclear reaction in which nuclei combine to form more massive nuclei with the simultaneous release of energy.

Question 41

Convex

Answer 41

Light curved outward like the outer surface of a sphere

Question 42

Concave

Answer 42

Light curved inward like the inner surface of a sphere

Question 43

Flat

Answer 43

no curved surface giving no curved image reflection

Question 44

Parabolic

Answer 44

a reflective device, formed in the shape of a parabolic dish; parabolic reflectors can either collect or distribute energy such as light, sound, or radio waves.