Unit 2- Test

Question 1

whats a molecular compound

Answer 1

pure substance formed between 2 nonmetals

Question 2

what kind of bond can molecular compounds be

Answer 2

single bond
double bond
triple bond

Question 3

what is bonding capacity

Answer 3

how many bonds an element needs to make

ex: C 4e- needs to make 4 bonds

Question 4

what element goes in the middle when drawing structural formula

Answer 4

atom with highest bonding capacity

Question 5

when does a coordinate covalent bond form

Answer 5

when both shared e- come from the same atom

ex: NH4

Question 6

What are 3 properties of molecular compunds

Answer 6

-low melting point
-do not conduct electricity
-can be solids, liquids, or gases at room temp.

Question 7

explain molecular compound property- low melting point

Answer 7

forces between separate molecules within substance are weak

Question 8

explain molecular compound property- do not conduct electricity

Answer 8

do not dissociate in water (unlike ionic)

Question 9

explain the consistency of a solid molecular compound & why its like that

Answer 9

soft, waxy, flexible
-molecules in solid can move relative to each other due to low attraction

Question 10

What is an ionic bond

Answer 10

when 2 oppositely charged ions are attracted to each other

Question 11

what do ionic compounds have…

Answer 11

fixed proportions of ions

Question 12

what is a formula unit

Answer 12

simplest whole # ratio of atoms or ions in an ionic compound

Question 13

how do ionic compounds arrange their atoms

Answer 13

crystal lattice
-cube where every atom is surrounded by an opposite charge

Question 14

what are 4 properties of ionic compounds

Answer 14

-hard
-brittle
-high melting/boiling point
-electrolytes

Question 15

explain ionic compound property- hard

Answer 15

strong attraction between cations and anions in crystal lattice

Question 16

explain ionic compound property- brittle

Answer 16

when ions shift, ions with like charges line up and repel eachother resulting in substance breaking apart

Question 17

explain ionic compound property- high melting/boiling point

Answer 17

strong electrostatic attraction between ions, must use lots of energy to break apart bonds

Question 18

explain ionic compound property- electrolytes

Answer 18

ions disassociate when dissolved in H2O

Question 19

what is a polar covalent bond

Answer 19

a covalent bond formed between atoms with different electronegativities

Question 20

ionic bond electronegativity difference

Answer 20

greater than 1.7

Question 21

polar covalent electronegativity diffrence

Answer 21

between 0.5-1.7

Question 22

non polar covalent electronegativity diffrence

Answer 22

less than 0.5

Question 23

what is a polar molecule

Answer 23

a molecule slightly positive at one end and slightly negative at the other end because of electronegativity difference

Question 24

what do hydrates decompose to

Answer 24

an ionic compound (anhydrous) and water when heated

Question 25

what do you measure ionic compounds in

Answer 25

formula units

Question 26

what do you measure molecular compounds

Answer 26

molecules

Question 27

whats a intramolecular force

Answer 27

forces between atoms WITHIN a compound

Question 28

whats a intermolecular force

Answer 28

attractive force BETWEEN molecules

Question 29

what are the 3 basic kinds of intermolecular forces

Answer 29

-dipole-dipole -london dispersion -hydrogen bonds

Question 30

what is a dipole-dipole force

Answer 30

-attractive force between polar molecules *The positive end of one molecule is attracted to the negative end of other molecules ex: H-Cl...HCl

Question 31

what is a london dispersion force

Answer 31

-attractive force between ALL molecules -ONLY force a nonpolar molecule has --> caused by the movement of e- so molecules with more e- have more LD forces

Question 32

What is a hydrogen bond force

Answer 32

*stronger version of dipole-dipole -Force between +ve H and highly electronegative F,O, or N -what gives H2O special properties

Question 33

what is the law of definite proportions

Answer 33

a specific compound always contains elements in the same proportions by mass

Question 34

what is empirical formula

Answer 34

the simpliest whole # ratio of atoms or ions

Question 35

what is molecular formula

Answer 35

express the actual number of atoms or ions in one formula unit or compound/molecule

Question 36

what does ending "ic mean"

Answer 36

bigger charge

Question 38

what is the “main” ion ending

Answer 38

ATE

Question 39

1 more oxygen endjng

Answer 39

per ate

Question 40

1 less oxygen ending

Answer 40

ite

Question 41

2 less oxygen ending

Answer 41

hypo ite