chemical bonding

Question 1

how are chemical compounds formed?

Answer 1

they form when atoms are bonded together
- have low potential energy when atoms are bonded

Question 2

endothermic

Answer 2

breaking a chemical bond
absorbs energy = cooler surroundings

Question 3

exothermic

Answer 3

forming a chemical bond
release energy = warmer surroundings

Question 4

low potential energy

Answer 4

compounds with strong stable bonds = dont release much energy when broken

Question 5

high potential energy

Answer 5

compounds with weak + unstable bonds = release moore energy

Question 6

what are the 2 kinds of compounds?

Answer 6

ionic (nonmetal + metal, cation +anion)
covalent

Question 7

ionic compounds

Answer 7

high + boiling points, dissolves in water, conducts electricity in solution

Question 8

covalent

Answer 8

low melting point + boiling point, DO NOT CONDUCT ELECTRICITY NOR DISSOLVE IN WATER

Question 9

What is a chemical bond?

Answer 9

formed when valance electrons are transferred (ionic) or shared (covalent) between atoms

Question 10

What is polarity?

Answer 10

distribution of electrons

polar = asymmetrical
non-polar = symmetrical

Question 11

what happens when an atom gains an electron?

Answer 11

radius increases because electrons are further away from the nucleus

Question 12

what happens when an atom loses an electron?

Answer 12

radius decreases = electrons closer to the nucleus

Question 13

how do atoms become stable?

Answer 13

by ionic bonds donating electrons and covalent bonds sharing electrons

Question 14

when are atoms stable

Answer 14

when they have a full valance shell (8 electrons)

exception: H only needs 2

Question 15

electronegativity

Answer 15

atoms attractions to electrons

Question 16

0.0-0.4

Answer 16

non polar covalent

Question 17

0.4-1.7

Answer 17

polar covalent

Question 18

higher than 1.7

Answer 18

ionic

Question 19

intermolecular forces

Answer 19

attractive forces that increase between the molecules of substances (elements + compounds) and responsible for physical + chemical properties

Question 20

hydrogen bonds

Answer 20

strong intermolecular forces

Question 21

FON means..

Answer 21

fluorine, oxygen, nitrogen

Question 22

substances with hydrogen bonds have…

Answer 22

high + boiling melting points

Question 23

dipole dipole

Answer 23

type of intermolecular force
positive + negative molecule

Question 24

do covalents share or donate?

Answer 24

share

Question 25

do ionics share or donate?

Answer 25

donate

Question 26

when bonds are formed they..

Answer 26

have lower potential energy because formed bonds released energy

Question 27

what are the forces between atoms that create chemical bonds?

Answer 27

due to attractions between protons + electrons

Question 28

polars are dipole dipole because..

Answer 28

they are asymmetrical due to unequal electrical charges (opposite)

Question 29

why are metallic good conductors of electricity?

Answer 29

due tot its valance electrons being stationary (they move freely)

Question 30

non polar COVALENTS are….

Answer 30

insoluble in water + low boiling points due to nonmetals