Physical and chemical properties and changes

Question 1

Density

Answer 1

the amount of mass present in a given volume, reflection of how tightly packed the atoms are

Example: Water has a density of 1 gram per cubic centimeter.

Question 2

Homogeneous mixture

Answer 2

a mixture with the same ratio of parts throughout the mixture

Example: salt dissolved in water

Question 3

physical change

Answer 3

a change in the appearance of a material with no change to its chemical composition

Example: phase change (water boiling)

Question 4

phase change

Answer 4

a change of state of a substance

Example: gas to liquid

Question 5

luster

Answer 5

the ability of the mineral’s surface to reflect light; can be metallic, submetallic, or nonmetallic

Example: galena has a metallic luster

Question 5

physical properties

Answer 5

properties that can be observed without changing the chemical makeup of the substance

Example: density, boiling point

Question 6

solubility

Answer 6

the ability of a substance to be dissolved in a solvent

Example: Table salt (NaCl) is highly soluble in water.

Question 7

electron

Answer 7

low-mass, negatively charged particle; surrounds the nucleus of an atom

Question 8

solute

Answer 8

the material in a solution that is dissolved in the solvent

Example: The sugar in lemonade

Question 9

Ionization Energy

Answer 9

the amount of energy needed to remove an outer electron to make a positive ion

Example: Alkali metals have low ionization energies, making them highly reactive.

Question 10

Nucleus (of the atom)

Answer 10

the positively charged, small, central core of an atom; made of protons and neutrons

Question 11

Concentration

Answer 11

concentration is the amount of solute dissolved in a solvent, usually expressed as moles of solute per liter of solution

Example: A 1M solution of sodium chloride (NaCl) contains 1 mole of NaCl dissolved in 1 liter of water.

Question 12

Polarity

Answer 12

the distribution of electric charge within a molecule, resulting in regions with partial positive and negative charges

Example: Water is a polar molecule with a partial positive charge on its hydrogens and a partial negative charge on its oxygen.

Question 13

element

Answer 13

an atom with a unique number of protons in its nucleus

Example: iron

Question 14

Hardness

Answer 14

the mineral’s resistance to scratching; measured on the Mohs scale, where talc, the softest mineral, has a score of 1 and diamond, the hardest, has a score of 10

Example: diamond is hard, talc is soft

Question 15

Intensive properties

Answer 15

properties that do not depend on the amount of substance present

Example: density, color, temperature

Question 16

Matter

Answer 16

anything that has mass and takes up space

Example: mud

Question 17

Extensive properties

Answer 17

properties that depend on the amount of substance present

Example: mass, volume, length

Question 18

Heterogeneous mixture

Answer 18

a mixture that is not uniformly mixed

Example: granola with raisins at the bottom

Question 19

Molecule

Answer 19

electrically neutral particle made of two or more atoms joined together by a molecular bond

Example: oxygen (O2) in the atmosphere

Question 20

State of matter

Answer 20

whether an element is a solid, liquid, or gas at given conditions

Example: Oxygen is a gas, mercury is a liquid, and iron is a solid at room temperature.

Question 21

Solution

Answer 21

a mixture in which one substance dissolves in another

Example: simple syrup (sugar and water)

Question 22

Proton

Answer 22

positively charged particle found in the nucleus of atoms

Question 23

Conductivity

Answer 23

the ability of a material to allow the flow of heat or electricity

Example: Copper is a good conductor of electricity.

Question 24

ionic Bond

Answer 24

a chemical bond between oppositely charged atoms when electrons are removed from one atom and given to an atom of another element Example: salt (NaCl)

Question 25

Malleability

Answer 25

the ability of a material to be hammered or pressed into shape without breaking Example: Gold is highly malleable and can be beaten into thin sheets.

Question 26

Pure Substance

Answer 26

a substance that consists of only one type of atom or molecule Example: helium gas

Question 27

Compound

Answer 27

groups of two or more different elements held together by ionic or molecular bonds Example: NaCl and H2O

Question 28

Volatility

Answer 28

how easily a substance turns into a vapor (gas) at a given temperature Example: helium & hydrogen are volatile

Question 29

atoms

Answer 29

the smallest unit of an element that has properties of that element Example: carbon atom

Question 30

Crystalline Structure

Answer 30

the degree to which the mineral is arranged in a crystal lattice structure; the more crystalline the mineral is, the harder that lattice is to see with the naked eye Example: Sodium chloride crystals typically have a cubic shape, while graphite has a layered sheet-like structure.

Question 31

Melting point / freezing point

Answer 31

temperature at which melting and freezing occur; a physical property of a substance Example: 32 degrees fahrenheit for water

Question 32

condensation

Answer 32

a phase change from the gas state to the liquid state Example: humidity condensing on a cold glass of tea

Question 33

Solvent

Answer 33

a substance which dissolves other substances Example: if salt is dissolved in water, water is the solvent.

Question 34

MIxture

Answer 34

a substance in which the atoms, molecules, or particles of two or more different materials are mixed but not chemically combined Example: salad

Question 35

boiling point

Answer 35

temperature at which evaporation and condensation occur; a physical property of a substance Example: 100 degrees celsius for water

Question 36

ground state

Answer 36

the lowest-energy arrangement of electrons in an atom

Question 37

Melting

Answer 37

A phase change from the solid state to the liquid state Example: mercury melts at -38 degrees fahrenheit

Question 38

Phase change temperatures

Answer 38

the temperatures at which an element changes from one state of matter to another (solid, liquid, gas) Example: The boiling, melting, and freezing points of a substance.

Question 39

Chemical change

Answer 39

a change that alters the chemical composition of a material Example: digestion (carbs breaking down into sugar)

Question 40

Freezing

Answer 40

a phase change from the liquid state to the solid state Example: coconut oil solidifies at 76 degrees fahrenheit

Question 41

Molecular bond / covalent bond

Answer 41

a chemical bond formed when two atoms share their outer electrons; formed between two nonmetal atoms Example: bond between carbon and oxygen (CO2)

Question 42

neutron

Answer 42

neutral particle found in the nucleus of atoms

Question 43

Chemical reaction

Answer 43

a reaction that forms a new substance by rearranging the atomic bonds between atoms. The process absorbs energy during bond-breaking and releases energy during bond-making.

Question 44

Ductility

Answer 44

the ability of a material to be drawn into thin wires Example: Copper is very ductile, hence its use in electrical wiring.

Question 45

Evaporation

Answer 45

a phase change from the liquid state to the gas state Example: water boils at 100°C at sea level

Question 46

Electronegativity

Answer 46

the tendency of an atom to attract electrons toward itself Example: Fluorine, Oxygen, Nitrogen, and Chlorine are the most electronegative elements, while Francium is the least.

Question 47

Magnetism

Answer 47

the response of a mineral when exposed to magnetic materials; a physical property Example: magnetite displays strong attraction to magnetic fields

Question 48

Texture

Answer 48

the feel, appearance, or consistency of the surface of a material