Chemical Bonds Quiz 1

Question 1

when a new bond is formed, energy is (released/absorbed)

Answer 1

RELEASED - making it an exothermic process

Question 2

when a bond is broken, energy is (released/absorbed)

Answer 2

ABSORBED- making it an endothermic process

Question 3

IT TAKES ENERGY TO BREAK A BOND

Answer 3

!!!!

Question 4

when does bonding occur?

Answer 4

when electrons are shared or transferred between atoms (all about valence electrons!!)

Question 5

the number of valence electrons involved determines the bonding ratio

Answer 5

life hack: CRISS CROSS oxidation states with subscripts

Question 6

Metallic Bonds

Answer 6

occur between metals

Question 7

Ionic Bonds

Answer 7

transfer of electrons between metals and non metals

Question 8

Covalent Bonds (x2)

Answer 8

sharing of electrons between nonmetals (two types: polar covalent and non polar covalent)

Question 9

_____atoms are surrounded by a sea of mobile electrons. this free electron behavior accounts for conductivity and magnetism.

Answer 9

METAL

Question 10

why are metallic bonds possible?

Answer 10

because metals have very few valence electrons with low ionization energies.

Question 11

why are metals malleable?

Answer 11

because the atoms are free to move to new locations while the “sea” of electrons still surround them.

Question 12

what does an IONIC BOND result from?

Answer 12

the attraction between two oppositely charged ions (metal and nm)
example: sodium and chlorine

Question 13

what are ionic compounds?

Answer 13

crystal lattices of positive and negative ions

Question 14

ALL COMPOUNDS WITH POLYATOMIC IONS HAVE BOTH COVALENT AND IONIC BONDING!!

Answer 14

!!!!

Question 15

what are ANIONS?

Answer 15

(ionic bonds) negatively charged- non metals and most polyatomic ions

Question 16

what are CATIONS?

Answer 16

(ionic bonds) positively charged - metals and few polyatomic ions

Question 17

why do ions bond to other ions?

Answer 17

SO THAT THE CHARGE IS NEUTRALIZED! also- each ion has a full octet of electrons

Question 18

characteristics of IONIC SOLIDS?

Answer 18

• very strong force holding oppositely charged ions together
• high melting point, high boiling point
• can dissolve in water and dissociate (ions come apart)
• the solution of ions can then conduct electricity (= electrolytes)

Question 19

molecular solids?

Answer 19

• formed by covalent bonding (either polar or non polar)
• form individual models which can attract to each other
• easily melted and boiled
• soft solids (wax, butter, ice)

Question 20

network solids?

Answer 20

• typically formed by non polar covalent bonding
• does NOT form separate molecules
• forms one single crystal made of nonmetal atoms connected by one continuous network of covalent bonds with no areas of weakness that can break apart.
• ex- quartz, diamonds, sapphires
• do not conduct electricity, poor conductors of heat
• hard but brittle

Question 21

in a single covalent bond ___ electrons are shared between two atoms

Answer 21

2

Question 22

atoms share _____ electrons to form a double bond

Answer 22

4

Question 23

atoms share ____ electrons to form a triple bond

Answer 23

6

Question 24

All ELECTRONS MUST BE PAIRED!!!

Answer 24

!!!

Question 25

Non Polar Covalent Bonds

Answer 25

electrons are shared equally and are just as likely to be found around either molecule

Question 26

Polar Covalent Bonds (H2O!!!)

Answer 26

electrons are shared UNEQUALLY and electrons are more likely to be around one atom (the more electronegative atom hogs the electrons!)

Question 27

POLARITY = ________

Answer 27

separation of positive and negative charge

Question 28

Non-Polar Bond=

Answer 28

bonding electrons are shared equally

Question 29

Polar Bond =

Answer 29

electrons are shared UNEQUALLY

Question 30

how do you determine if a bond is polar?

Answer 30

look at electronegativity difference (table s, subtract)

Question 31

all polar molecules contain polar covalent bonds but just because a molecule has polar covalent bonds doesnt mean it is a polar molecule.

Answer 31

!!!

Question 32

EN DIFFERENCE: | 1.7 (large) = Ionic

Answer 32

!!!

Question 33

Polarity in BOND vs. Polarity in MOLECULE

Answer 33

Polar Covalent Bonds: occur when the bond is between two atoms with different electronegativities Polar Molecules: must have polar covalent bonds and an asymetrical shape

Question 34

_____ are the forces that hold atoms together in compounds or molecules

Answer 34

chemical bonds