Covalent Bonds & Chemical Reactions

Question 1

Chemical reactions

Answer 1

When 2 or more atoms bond to form a molecule or when bonded atoms are broken.

Question 2

Reactants

Answer 2

Substance used in the beginning of chemical reaction (usually on the left side)

Question 3

Products

Answer 3

Substance at the end of chemical reaction (usually on the right side)

Question 4

{?}—>{?}

Answer 4

{reactants}—>{products}

Question 5

Balanced chemical equation

Answer 5

When the # of atoms of each element is the same on each side of the equation

Question 6

Compounds

Answer 6

2 or more different atoms (different elements) bonded together

Question 7

Mononuclear molecule

Answer 7

2 or more atoms (same element) bonded together

Question 8

Unidirecional arrow describe a …… chemical reaction

Answer 8

Irreversible

Question 9

Reaction w/ 2 arrows pointing both sides is a …… chemical reaction

Answer 9

Reversible

Question 10

Equilibrium

Answer 10

Reaction proceeds at same rate as reverse reaction

Question 11

Law of mass action ideal law of chemical equilibrium (formula)

Answer 11

[A]^a[B]^b (products)
K = ———–
[C]^c[D]^d (reactants)

Question 12

What ions means?

Answer 12

There is a net charge

Question 13

Cations

Answer 13

Positive ions formed by losing electrons

Question 14

Anions

Answer 14

Negative ions formed by gaining electrons

Question 15

Elemental name of anions

Answer 15

“-ide” in the end

Question 16

Electron transfer

Answer 16

Movement of electrons from one element to another

Question 17

Ionic bonds

Answer 17

Lose or gain or electrons formed by ions w/ opposite charges to balance each other w/ 0 net charge (ex.: NaCl)

Question 18

Electrolytes (certain salts)

Answer 18

Ions necessary for nerve impulse conduction, muscle contraction, and H2O balance. (Sports drinks & dietary supplements replace ions lost via sweating)

Question 19

Covalent bonds

Answer 19

Sharing of electrons between atoms (stronger and more common than ionic) (organic & inorganic)

Question 20

Covalent bonds commonly found in

Answer 20

Carbon-based organic molecules (like DNA & proteins)

Question 21

Maximum # of pair of electrons that covalent bonds can share

Answer 21

Up to 3

Question 22

Stronger connection (covalent bonds)

Answer 22

More covalent bonds between 2 atoms

Question 23

Single covalent bond

Answer 23

Sigma (ō)

Tetrahedral, sp3, free to rotate

Question 24

Double covalent bond

Answer 24

Sigma (ō) & pi

Trigonal planar, no rotation

Question 25

Triple covalent bond

Answer 25

Sigma (ō), pi, sigma (ō)

Linear, no rotation, rare

Question 26

Polar covalent bond

Answer 26

Electrons are unequally shared. Electrons are attracted more to one nucleus than the other, so slightly (ō+) or (ō-) charge is developed

Question 27

Electronegativity

Answer 27

Upper right side of periodic table. Electrons tend to spend more time near to their nucleus.

Question 28

Nonpolar covalent bonds

Answer 28

Between 2 atoms of same element or different elements that share electrons equally

Question 29

Would life as we know exist only w/ ionic and covalent bonds?

Answer 29

No, we need hydrogen bonds and Van Der Walls interactions

Question 30

Hydrogen bonds sustain

Answer 30

Water, stabilize proteins & DNA, building block of cells.

Question 31

Hydrogen bond

Answer 31

Polar molecule w/ H ō+ being attracted to a ō- (N or O) of another or same molecule

Question 32

Van der Waals interactions

Answer 32

Atoms or molecules close to each other creating a + & - inside the atom or molecule.

Question 33

Bonds strength in order (stronger to weaker)

Answer 33

Covalent, ionic, hydrogen, and Van der Waals.

Question 34

Halides

Answer 34

Elements in row 17 of periodic table. Form -1 anions (gain electron)

Question 35

Alkali & alkaline metals

Answer 35

Elements in row 1 & 2. Form +1 or +2 cations (lose electrons)

Question 36

Ionic bonds usually creates …..

Answer 36

Salts

Question 37

Ionic strength influenced by environment

Answer 37

Dry crystal—> strong

In H2O—> easily broken

Question 38

Covalent bonds (# of binding energy)

Answer 38

Between 100-300 kj/mol

Question 39

C-H & C-S (polarity)

Answer 39

Nonpolar

Question 40

Law of mass (LeChatlier’s principle)

Answer 40

Add of reac. or removing prod. drives reaction to right.

Add of prod. or removing reac. drives reaction to left.

Question 41

K=1
K=100
K=0.001
What happens?

Answer 41

K=1 (= prod. & reac.)
K=100 (favor product)
K=0.001 (favor reactant)

Question 42

Valence

Answer 42

of electrons in outermost shell of atom

Question 43

Valency

Answer 43

of electrons an atom needs to gain or lose to be stable.