2.2 Chemistry

Question 1

Chemistry

Answer 1

Study of matter

Question 2

Matter

Answer 2

Composed of elements

Question 3

Elements

Answer 3

Specific substance that can’t be broken down into simpler substances by chemical reactions

Question 4

Number of elements, naturally occurring, unstable

Answer 4

118, 94, 24

Question 5

Unstable elements

Answer 5

Don’t exist for very long and some can only be produced in extreme conditions such as in nuclear reactions or in particle accelerators

Question 6

Periodic table

Answer 6

First created by Dmitri Mendeleev. Includes important info about each of the elements and how they relate to one another

Question 7

Atom

Answer 7

Smallest component of an element that retains all of the chemical properties of that element

Question 8

Nucleus (chemistry)

Answer 8

Central region of an atom containing protons and neutrons in all elements heavier than hydrogen

Question 9

Protons

Answer 9

Positively charged particles found in the nucleus of an atom

Atoms have the same number of electrons and protons

Question 10

Neutrons

Answer 10

Particles with a mass but no charge found in the nucleus of all atoms heavier than hydrogen

The “glue” holding all of the protons in the nucleus of an atom

Question 11

Electrons

Answer 11

Negatively charged particles scattered around the nucleus of an atom

Atoms have the same number of electrons and protons

Question 12

Valance electrons

Answer 12

Found on outer electron shell of an atom and important for chemical reactions

Question 13

Atomic number

Answer 13

Number of protons

Question 14

Mass of an atom

Answer 14

Approximately equal to mass of protons and neutrons since electrons are about 1837 times smaller than protons

Question 15

Electric charge

Answer 15

Play a role in determining how electricity moves through a material

Question 16

Orbitals

Answer 16

Regions around the nucleus where there is a high probability of finding electrons

Not necessarily circular

Question 17

Electron subshells

Answer 17

S – spherical

P – 3 dumbbell shaped

D – 5 more complex

F - 7 more complex

Question 18

First electron shell

Answer 18

1 s-orbital that can hold 2 electrons

Question 19

Second electron shell

Answer 19

1 s-orbital and 3 p-orbitals, each hold 2 electrons for a total of 8 electrons

Question 20

Significance of row on periodic table

Answer 20

The row an element is placed indicates how many electron shells it contains

Question 21

Inert elements

Answer 21

Don’t react with other elements because they have full outer shell

Question 22

Compound

Answer 22

Different physical and chemical properties than the elements from which it’s made

Question 23

Isotopes

Answer 23

Elements that have same number of protons and electrons but different number of neutrons

Chemically identical but many have different stabilities

Some are radioactive

Question 24

Ionic bonds

Answer 24

Transfer of electrons between two atoms that creates a negative ion and positive ion with full outer shells.

Question 25

Ion

Answer 25

Atom with a charge

Question 26

Anion

Answer 26

Ion with negative charge

Question 27

Cation

Answer 27

Ion with a positive charge

Question 28

Covalent bonds

Answer 28

Elements share electrons to achieve a full outer shell (rather than gaining/losing electrons) Single, double, or triple

Question 29

Molecules

Answer 29

Resulting product of a covalent bond Smallest unit of a compound that had the same properties as the compound but not always a compound Don’t have to contain more than one element

Question 30

Compound

Answer 30

Result of bond between at least two different elements

Question 31

Nonpolar covalent bonds

Answer 31

Covalently bonded atoms that share electrons nearly equally

Question 32

Polar covalent bonds

Answer 32

Covalently bonded atoms that share electrons unequally due to a difference in electronegativity or charge

Question 33

Acid

Answer 33

Increases the concentration of hydrogen ions in a solution (low pH)

Question 34

Base

Answer 34

Provides hydroxide ions or other negatively charged ions that combine with hydrogen ions (high pH)

Question 35

pH

Answer 35

-log[H+] A pH difference of 1 indicates a 10x difference in hydrogen ions Indicates acidity or alkalinity <7 acidic 7 neutral >7 basic (alkaline)

Question 36

Octet

Answer 36

Full outer orbital

Question 37

Dipole

Answer 37

Created when a molecule has regions of charge that are separated

Question 38

Hydrogen bonds

Answer 38

Form between the partial positive charge on the hydrogen of one water molecule and the partial negative charge on the oxygen of another water molecule

Question 39

Dipole

Answer 39

Separated regions of charge on a molecule

Question 40

Universal solvent

Answer 40

Water, ions of an ionic molecule are more attracted to the water than to each other so they break apart and dissolve

Question 41

Cohesion

Answer 41

Attraction of a molecule to itself

Question 42

Adhesion

Answer 42

A molecule’s attraction to other substances