fundamentals of chemistry

Question 1

structure of atom

Answer 1

• smallest unit of element with central nucleus surrounded by one/more electrons
• nucleus: protons and neutrons held together by nuclear force
• atoms have no charge as protons and electrons cancel

Question 2

atomic mass

Answer 2

proton: 1
neutron: 1 but 0 charge

Question 3

isotopes

Answer 3

same protons different neutrons

Question 4

periodic table

Answer 4

column: groups
rows: periods

Question 5

atomic mass

Answer 5

protons + neutrons

Question 6

atomic number

Answer 6

protons

Question 7

molecular mass

Answer 7

total mass of atom: co2 = 44.01

Question 8

avogadros number

Answer 8

6.02 x 10 power 23

Question 9

amount of moles

Answer 9

amount (g) / molar mass (g/mol)

Question 10

molar

Answer 10

unit of concentration/volume

6mol/L = 6M

Question 11

different orbitals

Answer 11

s, p and d

Question 12

paul exclusion principle

Answer 12

any orbital can hold max 2 electrons, all p orbitals hold 9 electrons

Question 13

shells

Answer 13

1st shell (nucleus): 2 electrons 1s
2nd shell: 8 electrons 1s, 3p
3rd shell: 18 electrons 1s,3p, 5d

Question 14

subshells

Answer 14

2nd shell has 2 subshell 1s and 3p orbitals

Question 15

core electrons

Answer 15

filled shells closest to nucleus

Question 16

valence electrons

Answer 16

outer most shell, helps chemical reactions

Question 17

lewis dot structure

Answer 17

shows valence electrons
group corresponds with valence electrons
-can form dingle, double, triple bonds

Question 18

electronegativity

Answer 18

losing electrons

• estimates if bond is non-polar, covalent, polar covalent or ionic
• across period increases electronegativity as greater protons = greater attraction of electrons
• down a group decreases electronegativity as atoms have more electron shells so have bigger radius

Question 19

electron affinity

Answer 19

gaining electrons

Question 20

nonpolar

Answer 20

electrons shared equally

Question 21

polar

Answer 21

electrons shared unequally

Question 22

ionic bonds

Answer 22

electrons are transferred