Chemical Bonding

Question 1

Chemical bond

Answer 1

Formed to decrease potential energy and increase stability, attractive force between atoms/ions, binds together as unit

Question 2

Covalent bonds

Answer 2

Electrons are shared between atoms in molecules or polyatomic ions

Question 3

Ionic bonding

Answer 3

Cations and anions are attracted and held together by electrostatic forces

Question 4

Polar covalent

Answer 4

Unequal electron attraction, partially charged poles, asymmetric electron density

Question 5

Nonpolar covalent

Answer 5

Equal share of electrons, symmetrical electron density

Question 6

Which atom will pull electrons more?

Answer 6

The one with higher electronegativity

Question 7

What is the range of difference in electronegativity for a nonpolar covalent bond?

Answer 7

Less than or equal to 0.4

Question 8

What is the range of difference in electronegativity for a polar covalent bond?

Answer 8

(0.4,2.1]

Question 9

What is the range of difference in electronegativity for an ionic bond?

Answer 9

Greater than 2.1

Question 10

Crystaline solid

Answer 10

3D network of cations and anions with mutual attraction

Question 11

Lattice energy

Answer 11

Amount of energy given off by forming 1 mole of an ionic crystalline solid, indicates strength of ionic bonds

Question 12

Formula unit

Answer 12

Chemical formula for ionic compound, ratio of ions in crystalline structure

Question 13

Properties of ionic compounds

Answer 13

High melting and boiling points, most are solid at room temperature, hard, brittle, rigid, conduct electricity when molten or dissolved but not when solid

Question 14

Anion

Answer 14

Nonmetallic atoms that gained valence electrons

Question 15

Cation

Answer 15

Metallic atoms that lost valence electrons

Question 16

Polyatomic atom

Answer 16

Group of covalently bonded ions with a net charge for the group

Question 17

Mole

Answer 17

Amount of a substance with 6.022*10^23 particles, molar weight of an element is the atomic mass in grams

Question 18

Molar mass

Answer 18

Mass of 1 mol of a pure substance, g/mol

Question 19

amu

Answer 19

Atomic mass unit

Question 20

STP

Answer 20

Standard temperature and pressure, 0℃, 1 atmosphere

Question 21

What is the molar volume of gas at STP?

Answer 21

22.4L/mol

Question 22

Percent composition

Answer 22

Relative amounts of each element in a compound

Question 23

Empirical formula

Answer 23

Lowest whole number ratio of the atoms of an element in a compound

Question 24

Microscopic

Answer 24

Atoms

Question 25

Macroscopic

Answer 25

Moles

Question 26

How do you get the empirical formula of a compound from its percent composition?

Answer 26

Assume there are 100g of the compound so the percent is the amount of grams, divide the amount of element in grams by the element's atomic mass to get the amount of moles, divide all molar quantities by the smallest value (repeat or multiply all quantities to get whole numbers or close)

Question 27

How do you get the chemical formula from the empirical formula and molar mass?

Answer 27

Find the molar mass of the empirical formula, divide the molar mass of the compound by the molar mass of the empirical formula, multiply the empirical formula numbers by N (compound molar mass/empirical formula molar mass)

Question 28

Isolated atoms

Answer 28

Monatomic, single atoms

Question 29

Molecule

Answer 29

Smallest electrically neutral unit with properties, nonmetals, compound or just one element

Question 30

Molecular compounds

Answer 30

Low melt/boil points, usually gas/liquid, 2 or more nonmetals, unit is molecule

Question 31

Ionic compounds

Answer 31

From joining metallic cations and nonmetallic anions, electrically neutral, usually solid crystals, high melting temperature, unit is formula unit

Question 32

7 diatomic elements

Answer 32

Hydrogen, nitrogen, oxygen, fluorine, chlorine, bromine, iodine (BrINClHOF)

Question 33

Stock system

Answer 33

Uses roman numerals in parentheses to indicate numerical value (how much positive charge does a transition metal have)

Question 34

Which transition metals don't use Roman numerals and what are their charges?

Answer 34

Silver (Ag) = 1+ charge Cadmium (Cd) = 2+ charge Zinc (Zn) = 2+ charge

Question 35

Binary compounds

Answer 35

2 elements, ionic, name is 2 elements then change anion

Question 36

Molecular compounds

Answer 36

Only nonmetals, smallest is molecules, charges don't mean anything, name tells number

Question 37

Number prefixes

Answer 37

1 = mono- 2 = di- 3 = tri- 4 = tetra- 5 = penta- 6 = hexa- 7 = hepta- 8 = octa- 9 = nona- 10 = deca-

Question 38

Exceptions/changes to prefix usage

Answer 38

Don't use mono- for the first element if there's only one of them, avoid double vowels by removing the end vowel of the prefix except with di- and tri-