Science Test 3

Question 1

Matter

Answer 1

Everything that is around us. Matter must have mass and volume. Matter is made of tiny particles.

Question 2

Physical Properties

Answer 2

Can be observed or measured. Physical properties of the matter do not change its identity

Question 3

Chemical properties

Answer 3

Describe a substance based on its ability to change into a new substance with different properties. A chemical reaction cannot be easily reversed

Question 4

Solid

Answer 4

State where particles vibrate in place with minimal space between them, held together by strong forces.

Question 5

Liquid

Answer 5

State where particles slide past each other with moderate spacing and forces, allowing fluidity.

Question 6

Gas

Answer 6

State where particles move freely with large spaces between them and weak attractive forces.

Question 7

Melting

Answer 7

Solid to liquid (e.g., ice to water).

Question 8

Freezing

Answer 8

Liquid to solid (e.g. water to ice).

Question 9

Evaporation

Answer 9

Liquid to gas (e.g., water to vapor)

Question 10

Condensation

Answer 10

Gas to liquid (e.g., water droplets on a glass).

Question 11

Sublimation

Answer 11

Solid to gas (e.g., dry ice)

Question 12

Deposition

Answer 12

Gas to solid (e.g., frost)

Question 13

Atom

Answer 13

Basic unit of a chemical element, consisting of a nucleus (protons and neutrons) and electrons orbiting around it. It is the smallest part of an element that retains the properties of that element.

Question 14

Proton

Answer 14

Positively charged particle in the nucleus, defining the atomic number of an element.

Question 15

Neutron

Answer 15

Neutral particle in the nucleus, contributing to atomic mass.

Question 16

Electron

Answer 16

Negatively charged particle orbiting the nucleus; involved in bonding and reactivity.

Question 17

Energy Levels

Answer 17

Regions around the nucleus where electrons are located; each level has a maximum electron capacity (Shell 1 = 2, Shell 2 = 8, etc.)

Question 18

Electron Dot Diagram (Lewis Dot Structure)

Answer 18

Representation of an atom’s valence electrons as dots around the element’s symbol

Question 19

Valence Electrons

Answer 19

Electrons in the outermost energy level, determining bonding behavior.

Question 20

Ion

Answer 20

Atom or molecule with a net electric charge due to loss or gain of electrons.

Question 21

Isotope

Answer 21

Atoms of the same element with different numbers of neutrons, leading to different atomic masses.

Question 22

Pure Substance

Answer 22

Contains only one type of matter with specific physical and chemical properties. Can be an element or a compound.

Question 23

Element

Answer 23

Simplest form of a pure substance, made of only one type of atom.

Question 24

Compound

Answer 24

Pure substance made of two or more elements chemically bonded.

Question 25

Mixture

Answer 25

Combination of two or more pure substances that are not chemically bonded.

Question 26

Mechanical Mixture (Heterogeneous Mixture)

Answer 26

Mixture where ingredients can be seen separately (e.g., salad).

Question 27

Suspension

Answer 27

Cloudy mixture with visible particles dispersed within another substance, also heterogeneous.

Question 28

Solution (Homogeneous Mixture)

Answer 28

Uniform mixture where ingredients cannot be distinguished (e.g., saltwater).

Question 29

Atomic Number

Answer 29

Number of protons in an atom’s nucleus, defining the element’s identity.

Question 30

Mass Number

Answer 30

Sum of protons and neutrons in the nucleus; helps differentiate isotopes.

Question 31

Nucleus

Answer 31

Positively charged core of an atom, containing protons and neutrons.

Question 32

Periodic Table

Answer 32

Organized table of elements arranged by atomic number, showing recurring chemical properties.

Question 33

Radioactive

Answer 33

Describes atoms that spontaneously decay, emitting radiation (common in certain isotopes).