Compositions 7&8

Question 1

VECTOR

Answer 1

a quantity that is fully described by both magnitude and direction

Question 2

SCALAR

Answer 2

a quantity that is fully described by its magnitude

Question 3

RESULTANT FORCE

Answer 3

• when two or more vectors are added

- the result of combining the individual vectors together

Question 4

ACCELERATION

Answer 4

-the rate at which the velocity of an object is increasing
-the rate of acceleration of an object depends on the force being applied to the object as well as the mass of the object
-force/mass
the rate of acceleration is directly proportional to the force applied and inversely proportional to the mass of the given object. this means that as the force increases, so does the acceleration, and as the mass increases the acceleration reduces.

Question 5

NEWTON’S FIRST LAW OF MOTION

Answer 5

-every object in a state of uniform motion tends to remain in that state of motion unless an external force is applied to it
(inertia)
-an object at rests stays at rest and an object in motion stays in motion with the same speed unless acted upon by an unbalanced force

Question 6

NEWTON’S SECOND LAW OF MOTION

Answer 6

• the relationship between an object’s mass, its acceleration, and the applied force is F=MA
• acceleration is produced when a force acts on mass and the greater the mass of the object being accelerated, the greater amount of force needed to accelerate that object

Question 7

NEWTON’S THIRD LAW OF MOTION

Answer 7

for every action there is an equal and opposite reaction

Question 8

ELECTROSTATIC FORCE

Answer 8

-the attraction or repulsion of particles or objects because of their electric charge
-for atom model
main carriers of positive charge are protons, while the main carriers of negative charge are electrons.
every proton carries exactly the same amount of positive charge and every electron carries a negative charge exactly that of a proton
any particle with electric charge will exert a force on any other particle with a charge
two like electric charges, both positive or negative, repel each other along a straight line between their centers
two unlike charges, one positive, one negative, attract each other along a straight line joining their centers

Question 9

GRAVITATIONAL FORCE

Answer 9

-the force of mutual attraction between any two objects by virtue of their masses
-universal force, every object in this universe attracts every other object at all distances
ex. all objects on earth experience the force of gravity due to earth
the revolution of the earth and other planets around the sun is explained in terms of pull of gravity of the sun on the planets
all large-scale phenomena of the universe such as the formation and evolution of stars, galaxies and galactic clusters are explained in terms of gravitational forces

Question 10

WORK

Answer 10

when a force acts upon an object to cause a displacement of the object
3 key ingredients to work
-force
-displacement
-cause
in order for a force to qualify as having done work on an object, there must be a displacement and the force must cause the displacement

Question 11

ATOM

Answer 11

-three basic parts of an atom are electrons, protons, and neutrons
electrons are the smallest of the three particles. electrons are found in shells or orbitals that surround the nucleus of an atom
protons and neutrons are found in the nucleus , they group together in the center of the atom

Question 12

ION

Answer 12

when fewer or extra electrons are present in an atom it is called ion

Question 13

ISOTOPE

Answer 13

when an atom is missing a neutron or has an extra neutron, the atom is called an isotope

Question 14

PHOTOSYNTHESIS

Answer 14

-the process whereby plants using light energy from the sun convert carbon dioxide and water to glucose sugar and oxygen gas through series of reactions
carbon dioxide + water = light energy=> glucose +oxygen

Question 15

SOLUBILITY

Answer 15

the property of a solid, liquid, or gaseous chemical substance called solute to dissolve in a solid, liquid or gaseous solvent.
the solubility of a substance like sugar (the solute) increases as the temperature of the liquid (the solvent) increases
-forms homogeneous solution of the solute in the solvent

-basically if something dissolves in something else its soluble

Question 16

THERMAL CONDUCTIVITY

Answer 16

-a measure of how fast heat flows through an object
thermal energy(heat) causes atoms and molecules to move or vibrate
packing things closer together(increasing the density) increases the number of collisions between atoms and improves the thermal conductivity
moving things farther apart decreases the number of collisions and reduces thermal conductivity.
sand has a lot of space between grains(lower density) and therefore is a poor conductor of thermal energy

Question 17

PERIODIC TABLE OF ELEMENTS

Answer 17

• element is a substance made of same type of atoms
• a list of all known substances that make up the universe
• elements organized in rows, or periods by order of increasing atomic number, which equals to the number of protons in the atomic nucleus of each element
• elements organized in columns, or groups, based on similar physical characteristics and chemical behavior

Question 18

COMPOUNDS

Answer 18

-made of different elements
-2 or more different elements ex. CaCl2
-composed of two or more atoms that are chemically bonded together
the valence electrons( the outer shell) in each atom interact
atoms that are chemically bonded either share or donate valence electrons

Question 19

CHEMICAL BONDS

Answer 19

• involve the exchange or sharing of electrons

- a stable compound occurs when the total energy of the combination has lower energy than the separated atoms

Question 20

VALENCE ELECTRONS

Answer 20

-the outermost electrons
-are able to interact with other atoms
depending on how those electrons interact, either an ionic or covalent bond is formed, and the atoms fuse together to form a molecule

Question 21

MOLECULE

Answer 21

• 2 or more elements could be the same element

ex. O2

Question 22

COVALENT BOND

Answer 22

bond in which one or more pair of electrons are shared by two atoms

Question 23

IONIC BOND

Answer 23

bond in which one or more electrons from one atom are removed and attached to another atom

Question 24

CHANGES OF PHASE

Answer 24

• freezing
• melting
• condensation
• vaporization
• sublimation
• deposition

Question 25

WEATHERING

Answer 25

-refers to the process involved in the breaking of rocks
-chemical weathering
the decomposition or alteration of rocks and minerals through chemical process, primarily through oxidation(exposure to water) and dissolution by weak acids
-physical weathering
movement of the Earth and environment can break apart rock formations

Question 26

GAS MOLECULAR STRUCTURE

Answer 26

the particles are arranged at random and are so far apart that there is no force of attraction between them

Question 27

WATER DENSITY

Answer 27

hot and cold water are both liquid forms but they have different densities

cool water is more dense than warm water and stays at the bottom

Question 28

PHYSICAL CHANGE

Answer 28

those that do not alter the identity of the matter itself

• there is a difference in the appearance, smell without a change in composition
• exs. peanuts into peanut butter

Question 29

CHEMICAL CHANGE

Answer 29

do alter the identity of a substance

• a change in the composition of the substances in question
• exs. iron rusting, wood burning, copper turning to brass